pinctrl/pinconfig: add debug interface
This update adds a debugfs interface to modify a pin configuration
for a given state in the pinctrl map. This allows to modify the
configuration for a non-active state, typically sleep state.
This configuration is not applied right away, but only when the state
will be entered.
This solution is mandated for us by HW validation: in order
to test and verify several pin configurations during sleep without
recompiling the software.
Signed-off-by: Laurent Meunier <laurent.meunier@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/pinctrl/pinconf.c b/drivers/pinctrl/pinconf.c
index baee2cc..ac8d382 100644
--- a/drivers/pinctrl/pinconf.c
+++ b/drivers/pinctrl/pinconf.c
@@ -574,6 +574,207 @@
.release = single_release,
};
+/* 32bit read/write ressources */
+#define MAX_NAME_LEN 16
+char dbg_pinname[MAX_NAME_LEN]; /* shared: name of the state of the pin*/
+char dbg_state_name[MAX_NAME_LEN]; /* shared: state of the pin*/
+static u32 dbg_config; /* shared: config to be read/set for the pin & state*/
+
+static int pinconf_dbg_pinname_print(struct seq_file *s, void *d)
+{
+ if (strlen(dbg_pinname))
+ seq_printf(s, "%s\n", dbg_pinname);
+ else
+ seq_printf(s, "No pin name set\n");
+ return 0;
+}
+
+static int pinconf_dbg_pinname_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, pinconf_dbg_pinname_print, inode->i_private);
+}
+
+static int pinconf_dbg_pinname_write(struct file *file,
+ const char __user *user_buf, size_t count, loff_t *ppos)
+{
+ int err;
+
+ if (count > MAX_NAME_LEN)
+ return -EINVAL;
+
+ err = sscanf(user_buf, "%15s", dbg_pinname);
+
+ if (err != 1)
+ return -EINVAL;
+
+ return count;
+}
+
+static const struct file_operations pinconf_dbg_pinname_fops = {
+ .open = pinconf_dbg_pinname_open,
+ .write = pinconf_dbg_pinname_write,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+ .owner = THIS_MODULE,
+};
+
+static int pinconf_dbg_state_print(struct seq_file *s, void *d)
+{
+ if (strlen(dbg_state_name))
+ seq_printf(s, "%s\n", dbg_pinname);
+ else
+ seq_printf(s, "No pin state set\n");
+ return 0;
+}
+
+static int pinconf_dbg_state_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, pinconf_dbg_state_print, inode->i_private);
+}
+
+static int pinconf_dbg_state_write(struct file *file,
+ const char __user *user_buf, size_t count, loff_t *ppos)
+{
+ int err;
+
+ if (count > MAX_NAME_LEN)
+ return -EINVAL;
+
+ err = sscanf(user_buf, "%15s", dbg_state_name);
+
+ if (err != 1)
+ return -EINVAL;
+
+ return count;
+}
+
+static const struct file_operations pinconf_dbg_pinstate_fops = {
+ .open = pinconf_dbg_state_open,
+ .write = pinconf_dbg_state_write,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+ .owner = THIS_MODULE,
+};
+
+/**
+ * pinconf_dbg_config_print() - display the pinctrl config from the pinctrl
+ * map, of a pin/state pair based on pinname and state that have been
+ * selected with the debugfs entries pinconf-name and pinconf-state
+ * @s: contains the 32bits config to be written
+ * @d: not used
+ */
+static int pinconf_dbg_config_print(struct seq_file *s, void *d)
+{
+ struct pinctrl_maps *maps_node;
+ struct pinctrl_map const *map;
+ struct pinctrl_dev *pctldev = NULL;
+ struct pinconf_ops *confops = NULL;
+ int i, j;
+ bool found = false;
+
+ mutex_lock(&pinctrl_mutex);
+
+ /* Parse the pinctrl map and look for the elected pin/state */
+ for_each_maps(maps_node, i, map) {
+ if (map->type != PIN_MAP_TYPE_CONFIGS_PIN)
+ continue;
+
+ if (strncmp(map->name, dbg_state_name, MAX_NAME_LEN) > 0)
+ continue;
+
+ for (j = 0; j < map->data.configs.num_configs; j++) {
+ if (0 == strncmp(map->data.configs.group_or_pin,
+ dbg_pinname, MAX_NAME_LEN)) {
+ /* We found the right pin / state, read the
+ * config and store the pctldev */
+ dbg_config = map->data.configs.configs[j];
+ pctldev = get_pinctrl_dev_from_devname
+ (map->ctrl_dev_name);
+ found = true;
+ break;
+ }
+ }
+ }
+
+ mutex_unlock(&pinctrl_mutex);
+
+ if (found) {
+ seq_printf(s, "Config of %s in state %s: 0x%08X\n", dbg_pinname,
+ dbg_state_name, dbg_config);
+
+ if (pctldev)
+ confops = pctldev->desc->confops;
+
+ if (confops && confops->pin_config_config_dbg_show)
+ confops->pin_config_config_dbg_show(pctldev,
+ s, dbg_config);
+ } else {
+ seq_printf(s, "No pin found for defined name/state\n");
+ }
+
+ return 0;
+}
+
+static int pinconf_dbg_config_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, pinconf_dbg_config_print, inode->i_private);
+}
+
+/**
+ * pinconf_dbg_config_write() - overwrite the pinctrl config in thepinctrl
+ * map, of a pin/state pair based on pinname and state that have been
+ * selected with the debugfs entries pinconf-name and pinconf-state
+ */
+static int pinconf_dbg_config_write(struct file *file,
+ const char __user *user_buf, size_t count, loff_t *ppos)
+{
+ int err;
+ unsigned long config;
+ struct pinctrl_maps *maps_node;
+ struct pinctrl_map const *map;
+ int i, j;
+
+ err = kstrtoul_from_user(user_buf, count, 0, &config);
+
+ if (err)
+ return err;
+
+ dbg_config = config;
+
+ mutex_lock(&pinctrl_mutex);
+
+ /* Parse the pinctrl map and look for the selected pin/state */
+ for_each_maps(maps_node, i, map) {
+ if (map->type != PIN_MAP_TYPE_CONFIGS_PIN)
+ continue;
+
+ if (strncmp(map->name, dbg_state_name, MAX_NAME_LEN) > 0)
+ continue;
+
+ /* we found the right pin / state, so overwrite config */
+ for (j = 0; j < map->data.configs.num_configs; j++) {
+ if (strncmp(map->data.configs.group_or_pin, dbg_pinname,
+ MAX_NAME_LEN) == 0)
+ map->data.configs.configs[j] = dbg_config;
+ }
+ }
+
+ mutex_unlock(&pinctrl_mutex);
+
+ return count;
+}
+
+static const struct file_operations pinconf_dbg_pinconfig_fops = {
+ .open = pinconf_dbg_config_open,
+ .write = pinconf_dbg_config_write,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+ .owner = THIS_MODULE,
+};
+
void pinconf_init_device_debugfs(struct dentry *devroot,
struct pinctrl_dev *pctldev)
{
@@ -581,6 +782,12 @@
devroot, pctldev, &pinconf_pins_ops);
debugfs_create_file("pinconf-groups", S_IFREG | S_IRUGO,
devroot, pctldev, &pinconf_groups_ops);
+ debugfs_create_file("pinconf-name", (S_IRUGO | S_IWUSR | S_IWGRP),
+ devroot, pctldev, &pinconf_dbg_pinname_fops);
+ debugfs_create_file("pinconf-state", (S_IRUGO | S_IWUSR | S_IWGRP),
+ devroot, pctldev, &pinconf_dbg_pinstate_fops);
+ debugfs_create_file("pinconf-config", (S_IRUGO | S_IWUSR | S_IWGRP),
+ devroot, pctldev, &pinconf_dbg_pinconfig_fops);
}
#endif