Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Generic pwmlib implementation |
| 3 | * |
| 4 | * Copyright (C) 2011 Sascha Hauer <s.hauer@pengutronix.de> |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 5 | * Copyright (C) 2011-2012 Avionic Design GmbH |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify |
| 8 | * it under the terms of the GNU General Public License as published by |
| 9 | * the Free Software Foundation; either version 2, or (at your option) |
| 10 | * any later version. |
| 11 | * |
| 12 | * This program is distributed in the hope that it will be useful, |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | * GNU General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License |
| 18 | * along with this program; see the file COPYING. If not, write to |
| 19 | * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. |
| 20 | */ |
| 21 | |
| 22 | #include <linux/module.h> |
| 23 | #include <linux/pwm.h> |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 24 | #include <linux/radix-tree.h> |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 25 | #include <linux/list.h> |
| 26 | #include <linux/mutex.h> |
| 27 | #include <linux/err.h> |
| 28 | #include <linux/slab.h> |
| 29 | #include <linux/device.h> |
Thierry Reding | 62099ab | 2012-03-26 09:31:48 +0200 | [diff] [blame] | 30 | #include <linux/debugfs.h> |
| 31 | #include <linux/seq_file.h> |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 32 | |
Laurent Pinchart | 208be76 | 2013-07-18 00:54:22 +0200 | [diff] [blame] | 33 | #include <dt-bindings/pwm/pwm.h> |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 34 | |
Laurent Pinchart | 208be76 | 2013-07-18 00:54:22 +0200 | [diff] [blame] | 35 | #define MAX_PWMS 1024 |
Philip, Avinash | 83af240 | 2012-11-21 13:10:44 +0530 | [diff] [blame] | 36 | |
Thierry Reding | 8138d2d | 2012-03-26 08:42:48 +0200 | [diff] [blame] | 37 | static DEFINE_MUTEX(pwm_lookup_lock); |
| 38 | static LIST_HEAD(pwm_lookup_list); |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 39 | static DEFINE_MUTEX(pwm_lock); |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 40 | static LIST_HEAD(pwm_chips); |
| 41 | static DECLARE_BITMAP(allocated_pwms, MAX_PWMS); |
| 42 | static RADIX_TREE(pwm_tree, GFP_KERNEL); |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 43 | |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 44 | static struct pwm_device *pwm_to_device(unsigned int pwm) |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 45 | { |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 46 | return radix_tree_lookup(&pwm_tree, pwm); |
| 47 | } |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 48 | |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 49 | static int alloc_pwms(int pwm, unsigned int count) |
| 50 | { |
| 51 | unsigned int from = 0; |
| 52 | unsigned int start; |
| 53 | |
| 54 | if (pwm >= MAX_PWMS) |
| 55 | return -EINVAL; |
| 56 | |
| 57 | if (pwm >= 0) |
| 58 | from = pwm; |
| 59 | |
| 60 | start = bitmap_find_next_zero_area(allocated_pwms, MAX_PWMS, from, |
| 61 | count, 0); |
| 62 | |
| 63 | if (pwm >= 0 && start != pwm) |
| 64 | return -EEXIST; |
| 65 | |
| 66 | if (start + count > MAX_PWMS) |
| 67 | return -ENOSPC; |
| 68 | |
| 69 | return start; |
| 70 | } |
| 71 | |
| 72 | static void free_pwms(struct pwm_chip *chip) |
| 73 | { |
| 74 | unsigned int i; |
| 75 | |
| 76 | for (i = 0; i < chip->npwm; i++) { |
| 77 | struct pwm_device *pwm = &chip->pwms[i]; |
Thierry Reding | 83a9886 | 2016-05-02 12:05:55 +0200 | [diff] [blame] | 78 | |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 79 | radix_tree_delete(&pwm_tree, pwm->pwm); |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 80 | } |
| 81 | |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 82 | bitmap_clear(allocated_pwms, chip->base, chip->npwm); |
| 83 | |
| 84 | kfree(chip->pwms); |
| 85 | chip->pwms = NULL; |
| 86 | } |
| 87 | |
Thierry Reding | 8138d2d | 2012-03-26 08:42:48 +0200 | [diff] [blame] | 88 | static struct pwm_chip *pwmchip_find_by_name(const char *name) |
| 89 | { |
| 90 | struct pwm_chip *chip; |
| 91 | |
| 92 | if (!name) |
| 93 | return NULL; |
| 94 | |
| 95 | mutex_lock(&pwm_lock); |
| 96 | |
| 97 | list_for_each_entry(chip, &pwm_chips, list) { |
| 98 | const char *chip_name = dev_name(chip->dev); |
| 99 | |
| 100 | if (chip_name && strcmp(chip_name, name) == 0) { |
| 101 | mutex_unlock(&pwm_lock); |
| 102 | return chip; |
| 103 | } |
| 104 | } |
| 105 | |
| 106 | mutex_unlock(&pwm_lock); |
| 107 | |
| 108 | return NULL; |
| 109 | } |
| 110 | |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 111 | static int pwm_device_request(struct pwm_device *pwm, const char *label) |
| 112 | { |
| 113 | int err; |
| 114 | |
| 115 | if (test_bit(PWMF_REQUESTED, &pwm->flags)) |
| 116 | return -EBUSY; |
| 117 | |
| 118 | if (!try_module_get(pwm->chip->ops->owner)) |
| 119 | return -ENODEV; |
| 120 | |
| 121 | if (pwm->chip->ops->request) { |
| 122 | err = pwm->chip->ops->request(pwm->chip, pwm); |
| 123 | if (err) { |
| 124 | module_put(pwm->chip->ops->owner); |
| 125 | return err; |
| 126 | } |
| 127 | } |
| 128 | |
| 129 | set_bit(PWMF_REQUESTED, &pwm->flags); |
| 130 | pwm->label = label; |
| 131 | |
| 132 | return 0; |
| 133 | } |
| 134 | |
Philip, Avinash | 83af240 | 2012-11-21 13:10:44 +0530 | [diff] [blame] | 135 | struct pwm_device * |
| 136 | of_pwm_xlate_with_flags(struct pwm_chip *pc, const struct of_phandle_args *args) |
| 137 | { |
| 138 | struct pwm_device *pwm; |
| 139 | |
Lothar Wassmann | 42883cb | 2017-01-29 22:54:13 +0100 | [diff] [blame] | 140 | /* check, whether the driver supports a third cell for flags */ |
Philip, Avinash | 83af240 | 2012-11-21 13:10:44 +0530 | [diff] [blame] | 141 | if (pc->of_pwm_n_cells < 3) |
| 142 | return ERR_PTR(-EINVAL); |
| 143 | |
Lothar Wassmann | 42883cb | 2017-01-29 22:54:13 +0100 | [diff] [blame] | 144 | /* flags in the third cell are optional */ |
| 145 | if (args->args_count < 2) |
| 146 | return ERR_PTR(-EINVAL); |
| 147 | |
Philip, Avinash | 83af240 | 2012-11-21 13:10:44 +0530 | [diff] [blame] | 148 | if (args->args[0] >= pc->npwm) |
| 149 | return ERR_PTR(-EINVAL); |
| 150 | |
| 151 | pwm = pwm_request_from_chip(pc, args->args[0], NULL); |
| 152 | if (IS_ERR(pwm)) |
| 153 | return pwm; |
| 154 | |
Boris Brezillon | e39c0df | 2016-04-14 21:17:21 +0200 | [diff] [blame] | 155 | pwm->args.period = args->args[1]; |
Lothar Wassmann | 42883cb | 2017-01-29 22:54:13 +0100 | [diff] [blame] | 156 | pwm->args.polarity = PWM_POLARITY_NORMAL; |
Philip, Avinash | 83af240 | 2012-11-21 13:10:44 +0530 | [diff] [blame] | 157 | |
Lothar Wassmann | 42883cb | 2017-01-29 22:54:13 +0100 | [diff] [blame] | 158 | if (args->args_count > 2 && args->args[2] & PWM_POLARITY_INVERTED) |
Boris Brezillon | e39c0df | 2016-04-14 21:17:21 +0200 | [diff] [blame] | 159 | pwm->args.polarity = PWM_POLARITY_INVERSED; |
Philip, Avinash | 83af240 | 2012-11-21 13:10:44 +0530 | [diff] [blame] | 160 | |
| 161 | return pwm; |
| 162 | } |
Thierry Reding | 417328c | 2012-11-28 15:12:07 +0100 | [diff] [blame] | 163 | EXPORT_SYMBOL_GPL(of_pwm_xlate_with_flags); |
Philip, Avinash | 83af240 | 2012-11-21 13:10:44 +0530 | [diff] [blame] | 164 | |
Sachin Kamat | e50d352 | 2012-08-10 16:41:13 +0530 | [diff] [blame] | 165 | static struct pwm_device * |
| 166 | of_pwm_simple_xlate(struct pwm_chip *pc, const struct of_phandle_args *args) |
Thierry Reding | 7299ab7 | 2011-12-14 11:10:32 +0100 | [diff] [blame] | 167 | { |
| 168 | struct pwm_device *pwm; |
| 169 | |
Lothar Wassmann | 42883cb | 2017-01-29 22:54:13 +0100 | [diff] [blame] | 170 | /* sanity check driver support */ |
Thierry Reding | 7299ab7 | 2011-12-14 11:10:32 +0100 | [diff] [blame] | 171 | if (pc->of_pwm_n_cells < 2) |
| 172 | return ERR_PTR(-EINVAL); |
| 173 | |
Lothar Wassmann | 42883cb | 2017-01-29 22:54:13 +0100 | [diff] [blame] | 174 | /* all cells are required */ |
| 175 | if (args->args_count != pc->of_pwm_n_cells) |
| 176 | return ERR_PTR(-EINVAL); |
| 177 | |
Thierry Reding | 7299ab7 | 2011-12-14 11:10:32 +0100 | [diff] [blame] | 178 | if (args->args[0] >= pc->npwm) |
| 179 | return ERR_PTR(-EINVAL); |
| 180 | |
| 181 | pwm = pwm_request_from_chip(pc, args->args[0], NULL); |
| 182 | if (IS_ERR(pwm)) |
| 183 | return pwm; |
| 184 | |
Boris Brezillon | e39c0df | 2016-04-14 21:17:21 +0200 | [diff] [blame] | 185 | pwm->args.period = args->args[1]; |
Thierry Reding | 7299ab7 | 2011-12-14 11:10:32 +0100 | [diff] [blame] | 186 | |
| 187 | return pwm; |
| 188 | } |
| 189 | |
Sachin Kamat | dfeb86e | 2012-08-02 12:32:42 +0530 | [diff] [blame] | 190 | static void of_pwmchip_add(struct pwm_chip *chip) |
Thierry Reding | 7299ab7 | 2011-12-14 11:10:32 +0100 | [diff] [blame] | 191 | { |
| 192 | if (!chip->dev || !chip->dev->of_node) |
| 193 | return; |
| 194 | |
| 195 | if (!chip->of_xlate) { |
| 196 | chip->of_xlate = of_pwm_simple_xlate; |
| 197 | chip->of_pwm_n_cells = 2; |
| 198 | } |
| 199 | |
| 200 | of_node_get(chip->dev->of_node); |
| 201 | } |
| 202 | |
Sachin Kamat | dfeb86e | 2012-08-02 12:32:42 +0530 | [diff] [blame] | 203 | static void of_pwmchip_remove(struct pwm_chip *chip) |
Thierry Reding | 7299ab7 | 2011-12-14 11:10:32 +0100 | [diff] [blame] | 204 | { |
Markus Elfring | 8d6cc07 | 2015-02-03 11:54:28 +0100 | [diff] [blame] | 205 | if (chip->dev) |
Thierry Reding | 7299ab7 | 2011-12-14 11:10:32 +0100 | [diff] [blame] | 206 | of_node_put(chip->dev->of_node); |
| 207 | } |
| 208 | |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 209 | /** |
| 210 | * pwm_set_chip_data() - set private chip data for a PWM |
| 211 | * @pwm: PWM device |
| 212 | * @data: pointer to chip-specific data |
Thierry Reding | 0488380 | 2015-07-27 11:58:32 +0200 | [diff] [blame] | 213 | * |
| 214 | * Returns: 0 on success or a negative error code on failure. |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 215 | */ |
| 216 | int pwm_set_chip_data(struct pwm_device *pwm, void *data) |
| 217 | { |
| 218 | if (!pwm) |
| 219 | return -EINVAL; |
| 220 | |
| 221 | pwm->chip_data = data; |
| 222 | |
| 223 | return 0; |
| 224 | } |
Thierry Reding | 928c447 | 2013-01-30 09:22:24 +0100 | [diff] [blame] | 225 | EXPORT_SYMBOL_GPL(pwm_set_chip_data); |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 226 | |
| 227 | /** |
| 228 | * pwm_get_chip_data() - get private chip data for a PWM |
| 229 | * @pwm: PWM device |
Thierry Reding | 0488380 | 2015-07-27 11:58:32 +0200 | [diff] [blame] | 230 | * |
| 231 | * Returns: A pointer to the chip-private data for the PWM device. |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 232 | */ |
| 233 | void *pwm_get_chip_data(struct pwm_device *pwm) |
| 234 | { |
| 235 | return pwm ? pwm->chip_data : NULL; |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 236 | } |
Thierry Reding | 928c447 | 2013-01-30 09:22:24 +0100 | [diff] [blame] | 237 | EXPORT_SYMBOL_GPL(pwm_get_chip_data); |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 238 | |
Boris Brezillon | 5ec803e | 2016-04-14 21:17:41 +0200 | [diff] [blame] | 239 | static bool pwm_ops_check(const struct pwm_ops *ops) |
| 240 | { |
| 241 | /* driver supports legacy, non-atomic operation */ |
| 242 | if (ops->config && ops->enable && ops->disable) |
| 243 | return true; |
| 244 | |
| 245 | /* driver supports atomic operation */ |
| 246 | if (ops->apply) |
| 247 | return true; |
| 248 | |
| 249 | return false; |
| 250 | } |
| 251 | |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 252 | /** |
Tim Kryger | b6a00fa | 2015-05-26 13:08:16 -0700 | [diff] [blame] | 253 | * pwmchip_add_with_polarity() - register a new PWM chip |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 254 | * @chip: the PWM chip to add |
Tim Kryger | b6a00fa | 2015-05-26 13:08:16 -0700 | [diff] [blame] | 255 | * @polarity: initial polarity of PWM channels |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 256 | * |
| 257 | * Register a new PWM chip. If chip->base < 0 then a dynamically assigned base |
Tim Kryger | b6a00fa | 2015-05-26 13:08:16 -0700 | [diff] [blame] | 258 | * will be used. The initial polarity for all channels is specified by the |
| 259 | * @polarity parameter. |
Thierry Reding | 0488380 | 2015-07-27 11:58:32 +0200 | [diff] [blame] | 260 | * |
| 261 | * Returns: 0 on success or a negative error code on failure. |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 262 | */ |
Tim Kryger | b6a00fa | 2015-05-26 13:08:16 -0700 | [diff] [blame] | 263 | int pwmchip_add_with_polarity(struct pwm_chip *chip, |
| 264 | enum pwm_polarity polarity) |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 265 | { |
| 266 | struct pwm_device *pwm; |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 267 | unsigned int i; |
| 268 | int ret; |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 269 | |
Boris Brezillon | 5ec803e | 2016-04-14 21:17:41 +0200 | [diff] [blame] | 270 | if (!chip || !chip->dev || !chip->ops || !chip->npwm) |
| 271 | return -EINVAL; |
| 272 | |
| 273 | if (!pwm_ops_check(chip->ops)) |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 274 | return -EINVAL; |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 275 | |
| 276 | mutex_lock(&pwm_lock); |
| 277 | |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 278 | ret = alloc_pwms(chip->base, chip->npwm); |
| 279 | if (ret < 0) |
| 280 | goto out; |
| 281 | |
Thierry Reding | 2907f8a | 2016-05-02 12:07:34 +0200 | [diff] [blame] | 282 | chip->pwms = kcalloc(chip->npwm, sizeof(*pwm), GFP_KERNEL); |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 283 | if (!chip->pwms) { |
| 284 | ret = -ENOMEM; |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 285 | goto out; |
| 286 | } |
| 287 | |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 288 | chip->base = ret; |
| 289 | |
| 290 | for (i = 0; i < chip->npwm; i++) { |
| 291 | pwm = &chip->pwms[i]; |
| 292 | |
| 293 | pwm->chip = chip; |
| 294 | pwm->pwm = chip->base + i; |
| 295 | pwm->hwpwm = i; |
Boris Brezillon | 43a276b | 2016-04-14 21:17:38 +0200 | [diff] [blame] | 296 | pwm->state.polarity = polarity; |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 297 | |
Boris Brezillon | 15fa8a43 | 2016-04-14 21:17:40 +0200 | [diff] [blame] | 298 | if (chip->ops->get_state) |
| 299 | chip->ops->get_state(chip, pwm, &pwm->state); |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 300 | |
| 301 | radix_tree_insert(&pwm_tree, pwm->pwm, pwm); |
| 302 | } |
| 303 | |
| 304 | bitmap_set(allocated_pwms, chip->base, chip->npwm); |
| 305 | |
| 306 | INIT_LIST_HEAD(&chip->list); |
| 307 | list_add(&chip->list, &pwm_chips); |
| 308 | |
| 309 | ret = 0; |
| 310 | |
Thierry Reding | 7299ab7 | 2011-12-14 11:10:32 +0100 | [diff] [blame] | 311 | if (IS_ENABLED(CONFIG_OF)) |
| 312 | of_pwmchip_add(chip); |
| 313 | |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 314 | out: |
| 315 | mutex_unlock(&pwm_lock); |
Phong Hoang | 347ab94 | 2019-03-19 19:40:08 +0900 | [diff] [blame] | 316 | |
| 317 | if (!ret) |
| 318 | pwmchip_sysfs_export(chip); |
| 319 | |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 320 | return ret; |
| 321 | } |
Tim Kryger | b6a00fa | 2015-05-26 13:08:16 -0700 | [diff] [blame] | 322 | EXPORT_SYMBOL_GPL(pwmchip_add_with_polarity); |
| 323 | |
| 324 | /** |
| 325 | * pwmchip_add() - register a new PWM chip |
| 326 | * @chip: the PWM chip to add |
| 327 | * |
| 328 | * Register a new PWM chip. If chip->base < 0 then a dynamically assigned base |
| 329 | * will be used. The initial polarity for all channels is normal. |
Thierry Reding | 0488380 | 2015-07-27 11:58:32 +0200 | [diff] [blame] | 330 | * |
| 331 | * Returns: 0 on success or a negative error code on failure. |
Tim Kryger | b6a00fa | 2015-05-26 13:08:16 -0700 | [diff] [blame] | 332 | */ |
| 333 | int pwmchip_add(struct pwm_chip *chip) |
| 334 | { |
| 335 | return pwmchip_add_with_polarity(chip, PWM_POLARITY_NORMAL); |
| 336 | } |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 337 | EXPORT_SYMBOL_GPL(pwmchip_add); |
| 338 | |
| 339 | /** |
| 340 | * pwmchip_remove() - remove a PWM chip |
| 341 | * @chip: the PWM chip to remove |
| 342 | * |
| 343 | * Removes a PWM chip. This function may return busy if the PWM chip provides |
| 344 | * a PWM device that is still requested. |
Thierry Reding | 0488380 | 2015-07-27 11:58:32 +0200 | [diff] [blame] | 345 | * |
| 346 | * Returns: 0 on success or a negative error code on failure. |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 347 | */ |
| 348 | int pwmchip_remove(struct pwm_chip *chip) |
| 349 | { |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 350 | unsigned int i; |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 351 | int ret = 0; |
| 352 | |
Phong Hoang | 347ab94 | 2019-03-19 19:40:08 +0900 | [diff] [blame] | 353 | pwmchip_sysfs_unexport(chip); |
David Hsu | 0733424 | 2016-08-09 14:57:46 -0700 | [diff] [blame] | 354 | |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 355 | mutex_lock(&pwm_lock); |
| 356 | |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 357 | for (i = 0; i < chip->npwm; i++) { |
| 358 | struct pwm_device *pwm = &chip->pwms[i]; |
| 359 | |
| 360 | if (test_bit(PWMF_REQUESTED, &pwm->flags)) { |
| 361 | ret = -EBUSY; |
| 362 | goto out; |
| 363 | } |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 364 | } |
| 365 | |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 366 | list_del_init(&chip->list); |
Thierry Reding | 7299ab7 | 2011-12-14 11:10:32 +0100 | [diff] [blame] | 367 | |
| 368 | if (IS_ENABLED(CONFIG_OF)) |
| 369 | of_pwmchip_remove(chip); |
| 370 | |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 371 | free_pwms(chip); |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 372 | |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 373 | out: |
| 374 | mutex_unlock(&pwm_lock); |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 375 | return ret; |
| 376 | } |
| 377 | EXPORT_SYMBOL_GPL(pwmchip_remove); |
| 378 | |
| 379 | /** |
| 380 | * pwm_request() - request a PWM device |
Thierry Reding | 0488380 | 2015-07-27 11:58:32 +0200 | [diff] [blame] | 381 | * @pwm: global PWM device index |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 382 | * @label: PWM device label |
Thierry Reding | 8138d2d | 2012-03-26 08:42:48 +0200 | [diff] [blame] | 383 | * |
| 384 | * This function is deprecated, use pwm_get() instead. |
Thierry Reding | 0488380 | 2015-07-27 11:58:32 +0200 | [diff] [blame] | 385 | * |
| 386 | * Returns: A pointer to a PWM device or an ERR_PTR()-encoded error code on |
| 387 | * failure. |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 388 | */ |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 389 | struct pwm_device *pwm_request(int pwm, const char *label) |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 390 | { |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 391 | struct pwm_device *dev; |
| 392 | int err; |
| 393 | |
| 394 | if (pwm < 0 || pwm >= MAX_PWMS) |
| 395 | return ERR_PTR(-EINVAL); |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 396 | |
| 397 | mutex_lock(&pwm_lock); |
| 398 | |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 399 | dev = pwm_to_device(pwm); |
| 400 | if (!dev) { |
| 401 | dev = ERR_PTR(-EPROBE_DEFER); |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 402 | goto out; |
| 403 | } |
| 404 | |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 405 | err = pwm_device_request(dev, label); |
| 406 | if (err < 0) |
| 407 | dev = ERR_PTR(err); |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 408 | |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 409 | out: |
| 410 | mutex_unlock(&pwm_lock); |
| 411 | |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 412 | return dev; |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 413 | } |
| 414 | EXPORT_SYMBOL_GPL(pwm_request); |
| 415 | |
| 416 | /** |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 417 | * pwm_request_from_chip() - request a PWM device relative to a PWM chip |
| 418 | * @chip: PWM chip |
| 419 | * @index: per-chip index of the PWM to request |
| 420 | * @label: a literal description string of this PWM |
| 421 | * |
Thierry Reding | 0488380 | 2015-07-27 11:58:32 +0200 | [diff] [blame] | 422 | * Returns: A pointer to the PWM device at the given index of the given PWM |
| 423 | * chip. A negative error code is returned if the index is not valid for the |
| 424 | * specified PWM chip or if the PWM device cannot be requested. |
Thierry Reding | f051c46 | 2011-12-14 11:12:23 +0100 | [diff] [blame] | 425 | */ |
| 426 | struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip, |
| 427 | unsigned int index, |
| 428 | const char *label) |
| 429 | { |
| 430 | struct pwm_device *pwm; |
| 431 | int err; |
| 432 | |
| 433 | if (!chip || index >= chip->npwm) |
| 434 | return ERR_PTR(-EINVAL); |
| 435 | |
| 436 | mutex_lock(&pwm_lock); |
| 437 | pwm = &chip->pwms[index]; |
| 438 | |
| 439 | err = pwm_device_request(pwm, label); |
| 440 | if (err < 0) |
| 441 | pwm = ERR_PTR(err); |
| 442 | |
| 443 | mutex_unlock(&pwm_lock); |
| 444 | return pwm; |
| 445 | } |
| 446 | EXPORT_SYMBOL_GPL(pwm_request_from_chip); |
| 447 | |
| 448 | /** |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 449 | * pwm_free() - free a PWM device |
| 450 | * @pwm: PWM device |
Thierry Reding | 8138d2d | 2012-03-26 08:42:48 +0200 | [diff] [blame] | 451 | * |
| 452 | * This function is deprecated, use pwm_put() instead. |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 453 | */ |
| 454 | void pwm_free(struct pwm_device *pwm) |
| 455 | { |
Thierry Reding | 8138d2d | 2012-03-26 08:42:48 +0200 | [diff] [blame] | 456 | pwm_put(pwm); |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 457 | } |
| 458 | EXPORT_SYMBOL_GPL(pwm_free); |
| 459 | |
| 460 | /** |
Boris Brezillon | 5ec803e | 2016-04-14 21:17:41 +0200 | [diff] [blame] | 461 | * pwm_apply_state() - atomically apply a new state to a PWM device |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 462 | * @pwm: PWM device |
Boris Brezillon | 5ec803e | 2016-04-14 21:17:41 +0200 | [diff] [blame] | 463 | * @state: new state to apply. This can be adjusted by the PWM driver |
| 464 | * if the requested config is not achievable, for example, |
| 465 | * ->duty_cycle and ->period might be approximated. |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 466 | */ |
Boris Brezillon | 5ec803e | 2016-04-14 21:17:41 +0200 | [diff] [blame] | 467 | int pwm_apply_state(struct pwm_device *pwm, struct pwm_state *state) |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 468 | { |
H Hartley Sweeten | 76abbdde | 2013-06-11 10:38:59 -0700 | [diff] [blame] | 469 | int err; |
| 470 | |
Brian Norris | ef2bf49 | 2016-05-27 09:45:49 -0700 | [diff] [blame] | 471 | if (!pwm || !state || !state->period || |
| 472 | state->duty_cycle > state->period) |
Jonathan Richardson | d1cd214 | 2015-10-16 17:40:58 -0700 | [diff] [blame] | 473 | return -EINVAL; |
| 474 | |
Uwe Kleine-König | 309b32f | 2019-01-07 20:49:37 +0100 | [diff] [blame] | 475 | if (state->period == pwm->state.period && |
| 476 | state->duty_cycle == pwm->state.duty_cycle && |
| 477 | state->polarity == pwm->state.polarity && |
| 478 | state->enabled == pwm->state.enabled) |
Boris Brezillon | 5ec803e | 2016-04-14 21:17:41 +0200 | [diff] [blame] | 479 | return 0; |
Jonathan Richardson | d1cd214 | 2015-10-16 17:40:58 -0700 | [diff] [blame] | 480 | |
Boris Brezillon | 5ec803e | 2016-04-14 21:17:41 +0200 | [diff] [blame] | 481 | if (pwm->chip->ops->apply) { |
| 482 | err = pwm->chip->ops->apply(pwm->chip, pwm, state); |
Jonathan Richardson | d1cd214 | 2015-10-16 17:40:58 -0700 | [diff] [blame] | 483 | if (err) |
Boris Brezillon | 5ec803e | 2016-04-14 21:17:41 +0200 | [diff] [blame] | 484 | return err; |
| 485 | |
| 486 | pwm->state = *state; |
| 487 | } else { |
| 488 | /* |
| 489 | * FIXME: restore the initial state in case of error. |
| 490 | */ |
| 491 | if (state->polarity != pwm->state.polarity) { |
| 492 | if (!pwm->chip->ops->set_polarity) |
| 493 | return -ENOTSUPP; |
| 494 | |
| 495 | /* |
| 496 | * Changing the polarity of a running PWM is |
| 497 | * only allowed when the PWM driver implements |
| 498 | * ->apply(). |
| 499 | */ |
| 500 | if (pwm->state.enabled) { |
| 501 | pwm->chip->ops->disable(pwm->chip, pwm); |
| 502 | pwm->state.enabled = false; |
| 503 | } |
| 504 | |
| 505 | err = pwm->chip->ops->set_polarity(pwm->chip, pwm, |
| 506 | state->polarity); |
| 507 | if (err) |
| 508 | return err; |
| 509 | |
| 510 | pwm->state.polarity = state->polarity; |
| 511 | } |
| 512 | |
| 513 | if (state->period != pwm->state.period || |
| 514 | state->duty_cycle != pwm->state.duty_cycle) { |
| 515 | err = pwm->chip->ops->config(pwm->chip, pwm, |
| 516 | state->duty_cycle, |
| 517 | state->period); |
| 518 | if (err) |
| 519 | return err; |
| 520 | |
| 521 | pwm->state.duty_cycle = state->duty_cycle; |
| 522 | pwm->state.period = state->period; |
| 523 | } |
| 524 | |
| 525 | if (state->enabled != pwm->state.enabled) { |
| 526 | if (state->enabled) { |
| 527 | err = pwm->chip->ops->enable(pwm->chip, pwm); |
| 528 | if (err) |
| 529 | return err; |
| 530 | } else { |
| 531 | pwm->chip->ops->disable(pwm->chip, pwm); |
| 532 | } |
| 533 | |
| 534 | pwm->state.enabled = state->enabled; |
| 535 | } |
Jonathan Richardson | d1cd214 | 2015-10-16 17:40:58 -0700 | [diff] [blame] | 536 | } |
| 537 | |
Boris Brezillon | 5ec803e | 2016-04-14 21:17:41 +0200 | [diff] [blame] | 538 | return 0; |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 539 | } |
Boris Brezillon | 5ec803e | 2016-04-14 21:17:41 +0200 | [diff] [blame] | 540 | EXPORT_SYMBOL_GPL(pwm_apply_state); |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 541 | |
| 542 | /** |
Lee Jones | 3a3d1a4 | 2016-06-08 10:21:23 +0100 | [diff] [blame] | 543 | * pwm_capture() - capture and report a PWM signal |
| 544 | * @pwm: PWM device |
| 545 | * @result: structure to fill with capture result |
| 546 | * @timeout: time to wait, in milliseconds, before giving up on capture |
| 547 | * |
| 548 | * Returns: 0 on success or a negative error code on failure. |
| 549 | */ |
| 550 | int pwm_capture(struct pwm_device *pwm, struct pwm_capture *result, |
| 551 | unsigned long timeout) |
| 552 | { |
| 553 | int err; |
| 554 | |
| 555 | if (!pwm || !pwm->chip->ops) |
| 556 | return -EINVAL; |
| 557 | |
| 558 | if (!pwm->chip->ops->capture) |
| 559 | return -ENOSYS; |
| 560 | |
| 561 | mutex_lock(&pwm_lock); |
| 562 | err = pwm->chip->ops->capture(pwm->chip, pwm, result, timeout); |
| 563 | mutex_unlock(&pwm_lock); |
| 564 | |
| 565 | return err; |
| 566 | } |
| 567 | EXPORT_SYMBOL_GPL(pwm_capture); |
| 568 | |
| 569 | /** |
Boris Brezillon | 5ec803e | 2016-04-14 21:17:41 +0200 | [diff] [blame] | 570 | * pwm_adjust_config() - adjust the current PWM config to the PWM arguments |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 571 | * @pwm: PWM device |
Boris Brezillon | 5ec803e | 2016-04-14 21:17:41 +0200 | [diff] [blame] | 572 | * |
| 573 | * This function will adjust the PWM config to the PWM arguments provided |
| 574 | * by the DT or PWM lookup table. This is particularly useful to adapt |
| 575 | * the bootloader config to the Linux one. |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 576 | */ |
Boris Brezillon | 5ec803e | 2016-04-14 21:17:41 +0200 | [diff] [blame] | 577 | int pwm_adjust_config(struct pwm_device *pwm) |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 578 | { |
Boris Brezillon | 5ec803e | 2016-04-14 21:17:41 +0200 | [diff] [blame] | 579 | struct pwm_state state; |
| 580 | struct pwm_args pargs; |
Boris Brezillon | 09a7e4a | 2016-04-14 21:17:39 +0200 | [diff] [blame] | 581 | |
Boris Brezillon | 5ec803e | 2016-04-14 21:17:41 +0200 | [diff] [blame] | 582 | pwm_get_args(pwm, &pargs); |
| 583 | pwm_get_state(pwm, &state); |
| 584 | |
| 585 | /* |
| 586 | * If the current period is zero it means that either the PWM driver |
| 587 | * does not support initial state retrieval or the PWM has not yet |
| 588 | * been configured. |
| 589 | * |
| 590 | * In either case, we setup the new period and polarity, and assign a |
| 591 | * duty cycle of 0. |
| 592 | */ |
| 593 | if (!state.period) { |
| 594 | state.duty_cycle = 0; |
| 595 | state.period = pargs.period; |
| 596 | state.polarity = pargs.polarity; |
| 597 | |
| 598 | return pwm_apply_state(pwm, &state); |
Boris Brezillon | 09a7e4a | 2016-04-14 21:17:39 +0200 | [diff] [blame] | 599 | } |
Boris Brezillon | 5ec803e | 2016-04-14 21:17:41 +0200 | [diff] [blame] | 600 | |
| 601 | /* |
| 602 | * Adjust the PWM duty cycle/period based on the period value provided |
| 603 | * in PWM args. |
| 604 | */ |
| 605 | if (pargs.period != state.period) { |
| 606 | u64 dutycycle = (u64)state.duty_cycle * pargs.period; |
| 607 | |
| 608 | do_div(dutycycle, state.period); |
| 609 | state.duty_cycle = dutycycle; |
| 610 | state.period = pargs.period; |
| 611 | } |
| 612 | |
| 613 | /* |
| 614 | * If the polarity changed, we should also change the duty cycle. |
| 615 | */ |
| 616 | if (pargs.polarity != state.polarity) { |
| 617 | state.polarity = pargs.polarity; |
| 618 | state.duty_cycle = state.period - state.duty_cycle; |
| 619 | } |
| 620 | |
| 621 | return pwm_apply_state(pwm, &state); |
Sascha Hauer | 0c2498f | 2011-01-28 09:40:40 +0100 | [diff] [blame] | 622 | } |
Boris Brezillon | 5ec803e | 2016-04-14 21:17:41 +0200 | [diff] [blame] | 623 | EXPORT_SYMBOL_GPL(pwm_adjust_config); |
Thierry Reding | 62099ab | 2012-03-26 09:31:48 +0200 | [diff] [blame] | 624 | |
Thierry Reding | 7299ab7 | 2011-12-14 11:10:32 +0100 | [diff] [blame] | 625 | static struct pwm_chip *of_node_to_pwmchip(struct device_node *np) |
| 626 | { |
| 627 | struct pwm_chip *chip; |
| 628 | |
| 629 | mutex_lock(&pwm_lock); |
| 630 | |
| 631 | list_for_each_entry(chip, &pwm_chips, list) |
| 632 | if (chip->dev && chip->dev->of_node == np) { |
| 633 | mutex_unlock(&pwm_lock); |
| 634 | return chip; |
| 635 | } |
| 636 | |
| 637 | mutex_unlock(&pwm_lock); |
| 638 | |
| 639 | return ERR_PTR(-EPROBE_DEFER); |
| 640 | } |
| 641 | |
| 642 | /** |
Peter Ujfalusi | 8eb9612 | 2012-12-21 01:43:58 -0800 | [diff] [blame] | 643 | * of_pwm_get() - request a PWM via the PWM framework |
Thierry Reding | 7299ab7 | 2011-12-14 11:10:32 +0100 | [diff] [blame] | 644 | * @np: device node to get the PWM from |
| 645 | * @con_id: consumer name |
| 646 | * |
| 647 | * Returns the PWM device parsed from the phandle and index specified in the |
| 648 | * "pwms" property of a device tree node or a negative error-code on failure. |
| 649 | * Values parsed from the device tree are stored in the returned PWM device |
| 650 | * object. |
| 651 | * |
| 652 | * If con_id is NULL, the first PWM device listed in the "pwms" property will |
| 653 | * be requested. Otherwise the "pwm-names" property is used to do a reverse |
| 654 | * lookup of the PWM index. This also means that the "pwm-names" property |
| 655 | * becomes mandatory for devices that look up the PWM device via the con_id |
| 656 | * parameter. |
Thierry Reding | 0488380 | 2015-07-27 11:58:32 +0200 | [diff] [blame] | 657 | * |
| 658 | * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded |
| 659 | * error code on failure. |
Thierry Reding | 7299ab7 | 2011-12-14 11:10:32 +0100 | [diff] [blame] | 660 | */ |
Peter Ujfalusi | 8eb9612 | 2012-12-21 01:43:58 -0800 | [diff] [blame] | 661 | struct pwm_device *of_pwm_get(struct device_node *np, const char *con_id) |
Thierry Reding | 7299ab7 | 2011-12-14 11:10:32 +0100 | [diff] [blame] | 662 | { |
| 663 | struct pwm_device *pwm = NULL; |
| 664 | struct of_phandle_args args; |
| 665 | struct pwm_chip *pc; |
| 666 | int index = 0; |
| 667 | int err; |
| 668 | |
| 669 | if (con_id) { |
| 670 | index = of_property_match_string(np, "pwm-names", con_id); |
| 671 | if (index < 0) |
| 672 | return ERR_PTR(index); |
| 673 | } |
| 674 | |
| 675 | err = of_parse_phandle_with_args(np, "pwms", "#pwm-cells", index, |
| 676 | &args); |
| 677 | if (err) { |
Lothar Wassmann | f2dafc0 | 2017-01-29 22:54:05 +0100 | [diff] [blame] | 678 | pr_err("%s(): can't parse \"pwms\" property\n", __func__); |
Thierry Reding | 7299ab7 | 2011-12-14 11:10:32 +0100 | [diff] [blame] | 679 | return ERR_PTR(err); |
| 680 | } |
| 681 | |
| 682 | pc = of_node_to_pwmchip(args.np); |
| 683 | if (IS_ERR(pc)) { |
Jerome Brunet | 93c292e | 2017-05-23 18:05:03 +0200 | [diff] [blame] | 684 | if (PTR_ERR(pc) != -EPROBE_DEFER) |
| 685 | pr_err("%s(): PWM chip not found\n", __func__); |
| 686 | |
Thierry Reding | 7299ab7 | 2011-12-14 11:10:32 +0100 | [diff] [blame] | 687 | pwm = ERR_CAST(pc); |
| 688 | goto put; |
| 689 | } |
| 690 | |
Thierry Reding | 7299ab7 | 2011-12-14 11:10:32 +0100 | [diff] [blame] | 691 | pwm = pc->of_xlate(pc, &args); |
| 692 | if (IS_ERR(pwm)) |
| 693 | goto put; |
| 694 | |
| 695 | /* |
| 696 | * If a consumer name was not given, try to look it up from the |
| 697 | * "pwm-names" property if it exists. Otherwise use the name of |
| 698 | * the user device node. |
| 699 | */ |
| 700 | if (!con_id) { |
| 701 | err = of_property_read_string_index(np, "pwm-names", index, |
| 702 | &con_id); |
| 703 | if (err < 0) |
| 704 | con_id = np->name; |
| 705 | } |
| 706 | |
| 707 | pwm->label = con_id; |
| 708 | |
| 709 | put: |
| 710 | of_node_put(args.np); |
| 711 | |
| 712 | return pwm; |
| 713 | } |
Peter Ujfalusi | 8eb9612 | 2012-12-21 01:43:58 -0800 | [diff] [blame] | 714 | EXPORT_SYMBOL_GPL(of_pwm_get); |
Thierry Reding | 7299ab7 | 2011-12-14 11:10:32 +0100 | [diff] [blame] | 715 | |
Thierry Reding | 8138d2d | 2012-03-26 08:42:48 +0200 | [diff] [blame] | 716 | /** |
| 717 | * pwm_add_table() - register PWM device consumers |
| 718 | * @table: array of consumers to register |
| 719 | * @num: number of consumers in table |
| 720 | */ |
Shobhit Kumar | c264f11 | 2015-03-12 22:01:31 +0530 | [diff] [blame] | 721 | void pwm_add_table(struct pwm_lookup *table, size_t num) |
Thierry Reding | 8138d2d | 2012-03-26 08:42:48 +0200 | [diff] [blame] | 722 | { |
| 723 | mutex_lock(&pwm_lookup_lock); |
| 724 | |
| 725 | while (num--) { |
| 726 | list_add_tail(&table->list, &pwm_lookup_list); |
| 727 | table++; |
| 728 | } |
| 729 | |
| 730 | mutex_unlock(&pwm_lookup_lock); |
| 731 | } |
| 732 | |
| 733 | /** |
Shobhit Kumar | efb0de5 | 2015-05-05 15:04:18 +0530 | [diff] [blame] | 734 | * pwm_remove_table() - unregister PWM device consumers |
| 735 | * @table: array of consumers to unregister |
| 736 | * @num: number of consumers in table |
| 737 | */ |
| 738 | void pwm_remove_table(struct pwm_lookup *table, size_t num) |
| 739 | { |
| 740 | mutex_lock(&pwm_lookup_lock); |
| 741 | |
| 742 | while (num--) { |
| 743 | list_del(&table->list); |
| 744 | table++; |
| 745 | } |
| 746 | |
| 747 | mutex_unlock(&pwm_lookup_lock); |
| 748 | } |
| 749 | |
| 750 | /** |
Thierry Reding | 8138d2d | 2012-03-26 08:42:48 +0200 | [diff] [blame] | 751 | * pwm_get() - look up and request a PWM device |
| 752 | * @dev: device for PWM consumer |
| 753 | * @con_id: consumer name |
| 754 | * |
Thierry Reding | 7299ab7 | 2011-12-14 11:10:32 +0100 | [diff] [blame] | 755 | * Lookup is first attempted using DT. If the device was not instantiated from |
| 756 | * a device tree, a PWM chip and a relative index is looked up via a table |
| 757 | * supplied by board setup code (see pwm_add_table()). |
Thierry Reding | 8138d2d | 2012-03-26 08:42:48 +0200 | [diff] [blame] | 758 | * |
| 759 | * Once a PWM chip has been found the specified PWM device will be requested |
| 760 | * and is ready to be used. |
Thierry Reding | 0488380 | 2015-07-27 11:58:32 +0200 | [diff] [blame] | 761 | * |
| 762 | * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded |
| 763 | * error code on failure. |
Thierry Reding | 8138d2d | 2012-03-26 08:42:48 +0200 | [diff] [blame] | 764 | */ |
| 765 | struct pwm_device *pwm_get(struct device *dev, const char *con_id) |
| 766 | { |
Sachin Kamat | e50d352 | 2012-08-10 16:41:13 +0530 | [diff] [blame] | 767 | const char *dev_id = dev ? dev_name(dev) : NULL; |
Hans de Goede | 69efb34 | 2017-01-22 17:14:07 +0100 | [diff] [blame] | 768 | struct pwm_device *pwm; |
| 769 | struct pwm_chip *chip; |
Thierry Reding | 8138d2d | 2012-03-26 08:42:48 +0200 | [diff] [blame] | 770 | unsigned int best = 0; |
Geert Uytterhoeven | 70145f8 | 2014-08-28 11:03:14 +0200 | [diff] [blame] | 771 | struct pwm_lookup *p, *chosen = NULL; |
Thierry Reding | 8138d2d | 2012-03-26 08:42:48 +0200 | [diff] [blame] | 772 | unsigned int match; |
Hans de Goede | b526a31 | 2017-01-22 17:14:08 +0100 | [diff] [blame] | 773 | int err; |
Thierry Reding | 8138d2d | 2012-03-26 08:42:48 +0200 | [diff] [blame] | 774 | |
Thierry Reding | 7299ab7 | 2011-12-14 11:10:32 +0100 | [diff] [blame] | 775 | /* look up via DT first */ |
| 776 | if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node) |
Peter Ujfalusi | 8eb9612 | 2012-12-21 01:43:58 -0800 | [diff] [blame] | 777 | return of_pwm_get(dev->of_node, con_id); |
Thierry Reding | 7299ab7 | 2011-12-14 11:10:32 +0100 | [diff] [blame] | 778 | |
Thierry Reding | 8138d2d | 2012-03-26 08:42:48 +0200 | [diff] [blame] | 779 | /* |
| 780 | * We look up the provider in the static table typically provided by |
| 781 | * board setup code. We first try to lookup the consumer device by |
| 782 | * name. If the consumer device was passed in as NULL or if no match |
| 783 | * was found, we try to find the consumer by directly looking it up |
| 784 | * by name. |
| 785 | * |
| 786 | * If a match is found, the provider PWM chip is looked up by name |
| 787 | * and a PWM device is requested using the PWM device per-chip index. |
| 788 | * |
| 789 | * The lookup algorithm was shamelessly taken from the clock |
| 790 | * framework: |
| 791 | * |
| 792 | * We do slightly fuzzy matching here: |
| 793 | * An entry with a NULL ID is assumed to be a wildcard. |
| 794 | * If an entry has a device ID, it must match |
| 795 | * If an entry has a connection ID, it must match |
| 796 | * Then we take the most specific entry - with the following order |
| 797 | * of precedence: dev+con > dev only > con only. |
| 798 | */ |
| 799 | mutex_lock(&pwm_lookup_lock); |
| 800 | |
| 801 | list_for_each_entry(p, &pwm_lookup_list, list) { |
| 802 | match = 0; |
| 803 | |
| 804 | if (p->dev_id) { |
| 805 | if (!dev_id || strcmp(p->dev_id, dev_id)) |
| 806 | continue; |
| 807 | |
| 808 | match += 2; |
| 809 | } |
| 810 | |
| 811 | if (p->con_id) { |
| 812 | if (!con_id || strcmp(p->con_id, con_id)) |
| 813 | continue; |
| 814 | |
| 815 | match += 1; |
| 816 | } |
| 817 | |
| 818 | if (match > best) { |
Geert Uytterhoeven | 70145f8 | 2014-08-28 11:03:14 +0200 | [diff] [blame] | 819 | chosen = p; |
Thierry Reding | 8138d2d | 2012-03-26 08:42:48 +0200 | [diff] [blame] | 820 | |
| 821 | if (match != 3) |
| 822 | best = match; |
| 823 | else |
| 824 | break; |
| 825 | } |
| 826 | } |
| 827 | |
Hans de Goede | 69efb34 | 2017-01-22 17:14:07 +0100 | [diff] [blame] | 828 | mutex_unlock(&pwm_lookup_lock); |
| 829 | |
| 830 | if (!chosen) |
| 831 | return ERR_PTR(-ENODEV); |
Alexandre Belloni | 3796ce1 | 2014-05-19 22:42:32 +0200 | [diff] [blame] | 832 | |
Geert Uytterhoeven | 70145f8 | 2014-08-28 11:03:14 +0200 | [diff] [blame] | 833 | chip = pwmchip_find_by_name(chosen->provider); |
Hans de Goede | b526a31 | 2017-01-22 17:14:08 +0100 | [diff] [blame] | 834 | |
| 835 | /* |
| 836 | * If the lookup entry specifies a module, load the module and retry |
| 837 | * the PWM chip lookup. This can be used to work around driver load |
| 838 | * ordering issues if driver's can't be made to properly support the |
| 839 | * deferred probe mechanism. |
| 840 | */ |
| 841 | if (!chip && chosen->module) { |
| 842 | err = request_module(chosen->module); |
| 843 | if (err == 0) |
| 844 | chip = pwmchip_find_by_name(chosen->provider); |
| 845 | } |
| 846 | |
Geert Uytterhoeven | 70145f8 | 2014-08-28 11:03:14 +0200 | [diff] [blame] | 847 | if (!chip) |
Hans de Goede | 69efb34 | 2017-01-22 17:14:07 +0100 | [diff] [blame] | 848 | return ERR_PTR(-EPROBE_DEFER); |
Geert Uytterhoeven | 70145f8 | 2014-08-28 11:03:14 +0200 | [diff] [blame] | 849 | |
| 850 | pwm = pwm_request_from_chip(chip, chosen->index, con_id ?: dev_id); |
Alexandre Belloni | 3796ce1 | 2014-05-19 22:42:32 +0200 | [diff] [blame] | 851 | if (IS_ERR(pwm)) |
Hans de Goede | 69efb34 | 2017-01-22 17:14:07 +0100 | [diff] [blame] | 852 | return pwm; |
Thierry Reding | 8138d2d | 2012-03-26 08:42:48 +0200 | [diff] [blame] | 853 | |
Boris Brezillon | fbd45a1 | 2016-05-17 14:27:25 +0200 | [diff] [blame] | 854 | pwm->args.period = chosen->period; |
| 855 | pwm->args.polarity = chosen->polarity; |
| 856 | |
Thierry Reding | 8138d2d | 2012-03-26 08:42:48 +0200 | [diff] [blame] | 857 | return pwm; |
| 858 | } |
| 859 | EXPORT_SYMBOL_GPL(pwm_get); |
| 860 | |
| 861 | /** |
| 862 | * pwm_put() - release a PWM device |
| 863 | * @pwm: PWM device |
| 864 | */ |
| 865 | void pwm_put(struct pwm_device *pwm) |
| 866 | { |
| 867 | if (!pwm) |
| 868 | return; |
| 869 | |
| 870 | mutex_lock(&pwm_lock); |
| 871 | |
| 872 | if (!test_and_clear_bit(PWMF_REQUESTED, &pwm->flags)) { |
Sachin Kamat | e50d352 | 2012-08-10 16:41:13 +0530 | [diff] [blame] | 873 | pr_warn("PWM device already freed\n"); |
Thierry Reding | 8138d2d | 2012-03-26 08:42:48 +0200 | [diff] [blame] | 874 | goto out; |
| 875 | } |
| 876 | |
| 877 | if (pwm->chip->ops->free) |
| 878 | pwm->chip->ops->free(pwm->chip, pwm); |
| 879 | |
Uwe Kleine-König | e926b12 | 2019-03-25 10:49:33 +0100 | [diff] [blame] | 880 | pwm_set_chip_data(pwm, NULL); |
Thierry Reding | 8138d2d | 2012-03-26 08:42:48 +0200 | [diff] [blame] | 881 | pwm->label = NULL; |
| 882 | |
| 883 | module_put(pwm->chip->ops->owner); |
| 884 | out: |
| 885 | mutex_unlock(&pwm_lock); |
| 886 | } |
| 887 | EXPORT_SYMBOL_GPL(pwm_put); |
| 888 | |
Alexandre Courbot | 6354316 | 2012-08-01 19:20:58 +0900 | [diff] [blame] | 889 | static void devm_pwm_release(struct device *dev, void *res) |
| 890 | { |
| 891 | pwm_put(*(struct pwm_device **)res); |
| 892 | } |
| 893 | |
| 894 | /** |
| 895 | * devm_pwm_get() - resource managed pwm_get() |
| 896 | * @dev: device for PWM consumer |
| 897 | * @con_id: consumer name |
| 898 | * |
| 899 | * This function performs like pwm_get() but the acquired PWM device will |
| 900 | * automatically be released on driver detach. |
Thierry Reding | 0488380 | 2015-07-27 11:58:32 +0200 | [diff] [blame] | 901 | * |
| 902 | * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded |
| 903 | * error code on failure. |
Alexandre Courbot | 6354316 | 2012-08-01 19:20:58 +0900 | [diff] [blame] | 904 | */ |
| 905 | struct pwm_device *devm_pwm_get(struct device *dev, const char *con_id) |
| 906 | { |
| 907 | struct pwm_device **ptr, *pwm; |
| 908 | |
Wolfram Sang | 77f0b9d | 2013-06-03 22:27:17 +0200 | [diff] [blame] | 909 | ptr = devres_alloc(devm_pwm_release, sizeof(*ptr), GFP_KERNEL); |
Alexandre Courbot | 6354316 | 2012-08-01 19:20:58 +0900 | [diff] [blame] | 910 | if (!ptr) |
| 911 | return ERR_PTR(-ENOMEM); |
| 912 | |
| 913 | pwm = pwm_get(dev, con_id); |
| 914 | if (!IS_ERR(pwm)) { |
| 915 | *ptr = pwm; |
| 916 | devres_add(dev, ptr); |
| 917 | } else { |
| 918 | devres_free(ptr); |
| 919 | } |
| 920 | |
| 921 | return pwm; |
| 922 | } |
| 923 | EXPORT_SYMBOL_GPL(devm_pwm_get); |
| 924 | |
Peter Ujfalusi | 261a5ed | 2012-12-21 01:43:59 -0800 | [diff] [blame] | 925 | /** |
| 926 | * devm_of_pwm_get() - resource managed of_pwm_get() |
| 927 | * @dev: device for PWM consumer |
| 928 | * @np: device node to get the PWM from |
| 929 | * @con_id: consumer name |
| 930 | * |
| 931 | * This function performs like of_pwm_get() but the acquired PWM device will |
| 932 | * automatically be released on driver detach. |
Thierry Reding | 0488380 | 2015-07-27 11:58:32 +0200 | [diff] [blame] | 933 | * |
| 934 | * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded |
| 935 | * error code on failure. |
Peter Ujfalusi | 261a5ed | 2012-12-21 01:43:59 -0800 | [diff] [blame] | 936 | */ |
| 937 | struct pwm_device *devm_of_pwm_get(struct device *dev, struct device_node *np, |
| 938 | const char *con_id) |
| 939 | { |
| 940 | struct pwm_device **ptr, *pwm; |
| 941 | |
Wolfram Sang | 77f0b9d | 2013-06-03 22:27:17 +0200 | [diff] [blame] | 942 | ptr = devres_alloc(devm_pwm_release, sizeof(*ptr), GFP_KERNEL); |
Peter Ujfalusi | 261a5ed | 2012-12-21 01:43:59 -0800 | [diff] [blame] | 943 | if (!ptr) |
| 944 | return ERR_PTR(-ENOMEM); |
| 945 | |
| 946 | pwm = of_pwm_get(np, con_id); |
| 947 | if (!IS_ERR(pwm)) { |
| 948 | *ptr = pwm; |
| 949 | devres_add(dev, ptr); |
| 950 | } else { |
| 951 | devres_free(ptr); |
| 952 | } |
| 953 | |
| 954 | return pwm; |
| 955 | } |
| 956 | EXPORT_SYMBOL_GPL(devm_of_pwm_get); |
| 957 | |
Alexandre Courbot | 6354316 | 2012-08-01 19:20:58 +0900 | [diff] [blame] | 958 | static int devm_pwm_match(struct device *dev, void *res, void *data) |
| 959 | { |
| 960 | struct pwm_device **p = res; |
| 961 | |
| 962 | if (WARN_ON(!p || !*p)) |
| 963 | return 0; |
| 964 | |
| 965 | return *p == data; |
| 966 | } |
| 967 | |
| 968 | /** |
| 969 | * devm_pwm_put() - resource managed pwm_put() |
| 970 | * @dev: device for PWM consumer |
| 971 | * @pwm: PWM device |
| 972 | * |
| 973 | * Release a PWM previously allocated using devm_pwm_get(). Calling this |
| 974 | * function is usually not needed because devm-allocated resources are |
| 975 | * automatically released on driver detach. |
| 976 | */ |
| 977 | void devm_pwm_put(struct device *dev, struct pwm_device *pwm) |
| 978 | { |
| 979 | WARN_ON(devres_release(dev, devm_pwm_release, devm_pwm_match, pwm)); |
| 980 | } |
| 981 | EXPORT_SYMBOL_GPL(devm_pwm_put); |
| 982 | |
Thierry Reding | 62099ab | 2012-03-26 09:31:48 +0200 | [diff] [blame] | 983 | #ifdef CONFIG_DEBUG_FS |
| 984 | static void pwm_dbg_show(struct pwm_chip *chip, struct seq_file *s) |
| 985 | { |
| 986 | unsigned int i; |
| 987 | |
| 988 | for (i = 0; i < chip->npwm; i++) { |
| 989 | struct pwm_device *pwm = &chip->pwms[i]; |
Boris Brezillon | 39100ce | 2016-04-14 21:17:43 +0200 | [diff] [blame] | 990 | struct pwm_state state; |
| 991 | |
| 992 | pwm_get_state(pwm, &state); |
Thierry Reding | 62099ab | 2012-03-26 09:31:48 +0200 | [diff] [blame] | 993 | |
| 994 | seq_printf(s, " pwm-%-3d (%-20.20s):", i, pwm->label); |
| 995 | |
| 996 | if (test_bit(PWMF_REQUESTED, &pwm->flags)) |
Jingoo Han | adcba1e | 2013-12-19 13:31:24 +0900 | [diff] [blame] | 997 | seq_puts(s, " requested"); |
Thierry Reding | 62099ab | 2012-03-26 09:31:48 +0200 | [diff] [blame] | 998 | |
Boris Brezillon | 39100ce | 2016-04-14 21:17:43 +0200 | [diff] [blame] | 999 | if (state.enabled) |
Jingoo Han | adcba1e | 2013-12-19 13:31:24 +0900 | [diff] [blame] | 1000 | seq_puts(s, " enabled"); |
Thierry Reding | 62099ab | 2012-03-26 09:31:48 +0200 | [diff] [blame] | 1001 | |
Heiko Stübner | 23e3523 | 2016-04-14 21:17:44 +0200 | [diff] [blame] | 1002 | seq_printf(s, " period: %u ns", state.period); |
| 1003 | seq_printf(s, " duty: %u ns", state.duty_cycle); |
| 1004 | seq_printf(s, " polarity: %s", |
| 1005 | state.polarity ? "inverse" : "normal"); |
| 1006 | |
Jingoo Han | adcba1e | 2013-12-19 13:31:24 +0900 | [diff] [blame] | 1007 | seq_puts(s, "\n"); |
Thierry Reding | 62099ab | 2012-03-26 09:31:48 +0200 | [diff] [blame] | 1008 | } |
| 1009 | } |
| 1010 | |
| 1011 | static void *pwm_seq_start(struct seq_file *s, loff_t *pos) |
| 1012 | { |
| 1013 | mutex_lock(&pwm_lock); |
| 1014 | s->private = ""; |
| 1015 | |
| 1016 | return seq_list_start(&pwm_chips, *pos); |
| 1017 | } |
| 1018 | |
| 1019 | static void *pwm_seq_next(struct seq_file *s, void *v, loff_t *pos) |
| 1020 | { |
| 1021 | s->private = "\n"; |
| 1022 | |
| 1023 | return seq_list_next(v, &pwm_chips, pos); |
| 1024 | } |
| 1025 | |
| 1026 | static void pwm_seq_stop(struct seq_file *s, void *v) |
| 1027 | { |
| 1028 | mutex_unlock(&pwm_lock); |
| 1029 | } |
| 1030 | |
| 1031 | static int pwm_seq_show(struct seq_file *s, void *v) |
| 1032 | { |
| 1033 | struct pwm_chip *chip = list_entry(v, struct pwm_chip, list); |
| 1034 | |
| 1035 | seq_printf(s, "%s%s/%s, %d PWM device%s\n", (char *)s->private, |
| 1036 | chip->dev->bus ? chip->dev->bus->name : "no-bus", |
| 1037 | dev_name(chip->dev), chip->npwm, |
| 1038 | (chip->npwm != 1) ? "s" : ""); |
| 1039 | |
Uwe Kleine-König | cc2d224 | 2019-01-07 20:49:39 +0100 | [diff] [blame] | 1040 | pwm_dbg_show(chip, s); |
Thierry Reding | 62099ab | 2012-03-26 09:31:48 +0200 | [diff] [blame] | 1041 | |
| 1042 | return 0; |
| 1043 | } |
| 1044 | |
| 1045 | static const struct seq_operations pwm_seq_ops = { |
| 1046 | .start = pwm_seq_start, |
| 1047 | .next = pwm_seq_next, |
| 1048 | .stop = pwm_seq_stop, |
| 1049 | .show = pwm_seq_show, |
| 1050 | }; |
| 1051 | |
| 1052 | static int pwm_seq_open(struct inode *inode, struct file *file) |
| 1053 | { |
| 1054 | return seq_open(file, &pwm_seq_ops); |
| 1055 | } |
| 1056 | |
| 1057 | static const struct file_operations pwm_debugfs_ops = { |
| 1058 | .owner = THIS_MODULE, |
| 1059 | .open = pwm_seq_open, |
| 1060 | .read = seq_read, |
| 1061 | .llseek = seq_lseek, |
| 1062 | .release = seq_release, |
| 1063 | }; |
| 1064 | |
| 1065 | static int __init pwm_debugfs_init(void) |
| 1066 | { |
| 1067 | debugfs_create_file("pwm", S_IFREG | S_IRUGO, NULL, NULL, |
| 1068 | &pwm_debugfs_ops); |
| 1069 | |
| 1070 | return 0; |
| 1071 | } |
Thierry Reding | 62099ab | 2012-03-26 09:31:48 +0200 | [diff] [blame] | 1072 | subsys_initcall(pwm_debugfs_init); |
| 1073 | #endif /* CONFIG_DEBUG_FS */ |