mmc: sh_mmcif: switch to completion, fix flags
In sh_mmcif.c an event is used as a completion, switch over. When a
wait_for_completion*_timeout() returns, it suffices to check the remaining
time, setting an additional flag before waking up the waiting task only reduces
the race window, but does not eliminate it. This patch switches the driver to
use a completion to signal an interrupt, the only case, when an interrupt
should not wake up the waiter, is when an automatic CMD12 completes. Also fix
MODULE_ALIAS.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/drivers/mmc/host/sh_mmcif.c b/drivers/mmc/host/sh_mmcif.c
index 3f49273..74e7aca 100644
--- a/drivers/mmc/host/sh_mmcif.c
+++ b/drivers/mmc/host/sh_mmcif.c
@@ -16,6 +16,8 @@
*
*/
+#include <linux/clk.h>
+#include <linux/completion.h>
#include <linux/dma-mapping.h>
#include <linux/mmc/host.h>
#include <linux/mmc/card.h>
@@ -24,7 +26,6 @@
#include <linux/mmc/sdio.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
-#include <linux/clk.h>
#include <linux/mmc/sh_mmcif.h>
#define DRIVER_NAME "sh_mmcif"
@@ -158,11 +159,10 @@
struct clk *hclk;
unsigned int clk;
int bus_width;
- u16 wait_int;
- u16 sd_error;
+ bool sd_error;
long timeout;
void __iomem *addr;
- wait_queue_head_t intr_wait;
+ struct completion intr_wait;
};
@@ -216,8 +216,7 @@
u32 state1, state2;
int ret, timeout = 10000000;
- host->sd_error = 0;
- host->wait_int = 0;
+ host->sd_error = false;
state1 = sh_mmcif_readl(host->addr, MMCIF_CE_HOST_STS1);
state2 = sh_mmcif_readl(host->addr, MMCIF_CE_HOST_STS2);
@@ -264,17 +263,13 @@
long time;
u32 blocksize, i, *p = sg_virt(data->sg);
- host->wait_int = 0;
-
/* buf read enable */
sh_mmcif_bitset(host, MMCIF_CE_INT_MASK, MASK_MBUFREN);
- time = wait_event_interruptible_timeout(host->intr_wait,
- host->wait_int == 1 ||
- host->sd_error == 1, host->timeout);
- if (host->wait_int != 1 && (time == 0 || host->sd_error != 0))
+ time = wait_for_completion_interruptible_timeout(&host->intr_wait,
+ host->timeout);
+ if (time <= 0 || host->sd_error)
return sh_mmcif_error_manage(host);
- host->wait_int = 0;
blocksize = (BLOCK_SIZE_MASK &
sh_mmcif_readl(host->addr, MMCIF_CE_BLOCK_SET)) + 3;
for (i = 0; i < blocksize / 4; i++)
@@ -282,13 +277,11 @@
/* buffer read end */
sh_mmcif_bitset(host, MMCIF_CE_INT_MASK, MASK_MBUFRE);
- time = wait_event_interruptible_timeout(host->intr_wait,
- host->wait_int == 1 ||
- host->sd_error == 1, host->timeout);
- if (host->wait_int != 1 && (time == 0 || host->sd_error != 0))
+ time = wait_for_completion_interruptible_timeout(&host->intr_wait,
+ host->timeout);
+ if (time <= 0 || host->sd_error)
return sh_mmcif_error_manage(host);
- host->wait_int = 0;
return 0;
}
@@ -303,19 +296,15 @@
MMCIF_CE_BLOCK_SET);
for (j = 0; j < data->sg_len; j++) {
p = sg_virt(data->sg);
- host->wait_int = 0;
for (sec = 0; sec < data->sg->length / blocksize; sec++) {
sh_mmcif_bitset(host, MMCIF_CE_INT_MASK, MASK_MBUFREN);
/* buf read enable */
- time = wait_event_interruptible_timeout(host->intr_wait,
- host->wait_int == 1 ||
- host->sd_error == 1, host->timeout);
+ time = wait_for_completion_interruptible_timeout(&host->intr_wait,
+ host->timeout);
- if (host->wait_int != 1 &&
- (time == 0 || host->sd_error != 0))
+ if (time <= 0 || host->sd_error)
return sh_mmcif_error_manage(host);
- host->wait_int = 0;
for (i = 0; i < blocksize / 4; i++)
*p++ = sh_mmcif_readl(host->addr,
MMCIF_CE_DATA);
@@ -333,17 +322,14 @@
long time;
u32 blocksize, i, *p = sg_virt(data->sg);
- host->wait_int = 0;
sh_mmcif_bitset(host, MMCIF_CE_INT_MASK, MASK_MBUFWEN);
/* buf write enable */
- time = wait_event_interruptible_timeout(host->intr_wait,
- host->wait_int == 1 ||
- host->sd_error == 1, host->timeout);
- if (host->wait_int != 1 && (time == 0 || host->sd_error != 0))
+ time = wait_for_completion_interruptible_timeout(&host->intr_wait,
+ host->timeout);
+ if (time <= 0 || host->sd_error)
return sh_mmcif_error_manage(host);
- host->wait_int = 0;
blocksize = (BLOCK_SIZE_MASK &
sh_mmcif_readl(host->addr, MMCIF_CE_BLOCK_SET)) + 3;
for (i = 0; i < blocksize / 4; i++)
@@ -352,13 +338,11 @@
/* buffer write end */
sh_mmcif_bitset(host, MMCIF_CE_INT_MASK, MASK_MDTRANE);
- time = wait_event_interruptible_timeout(host->intr_wait,
- host->wait_int == 1 ||
- host->sd_error == 1, host->timeout);
- if (host->wait_int != 1 && (time == 0 || host->sd_error != 0))
+ time = wait_for_completion_interruptible_timeout(&host->intr_wait,
+ host->timeout);
+ if (time <= 0 || host->sd_error)
return sh_mmcif_error_manage(host);
- host->wait_int = 0;
return 0;
}
@@ -374,19 +358,15 @@
for (j = 0; j < data->sg_len; j++) {
p = sg_virt(data->sg);
- host->wait_int = 0;
for (sec = 0; sec < data->sg->length / blocksize; sec++) {
sh_mmcif_bitset(host, MMCIF_CE_INT_MASK, MASK_MBUFWEN);
/* buf write enable*/
- time = wait_event_interruptible_timeout(host->intr_wait,
- host->wait_int == 1 ||
- host->sd_error == 1, host->timeout);
+ time = wait_for_completion_interruptible_timeout(&host->intr_wait,
+ host->timeout);
- if (host->wait_int != 1 &&
- (time == 0 || host->sd_error != 0))
+ if (time <= 0 || host->sd_error)
return sh_mmcif_error_manage(host);
- host->wait_int = 0;
for (i = 0; i < blocksize / 4; i++)
sh_mmcif_writel(host->addr,
MMCIF_CE_DATA, *p++);
@@ -556,13 +536,12 @@
sh_mmcif_writel(host->addr, MMCIF_CE_INT_MASK, mask);
/* set arg */
sh_mmcif_writel(host->addr, MMCIF_CE_ARG, cmd->arg);
- host->wait_int = 0;
/* set cmd */
sh_mmcif_writel(host->addr, MMCIF_CE_CMD_SET, opc);
- time = wait_event_interruptible_timeout(host->intr_wait,
- host->wait_int == 1 || host->sd_error == 1, host->timeout);
- if (host->wait_int != 1 && time == 0) {
+ time = wait_for_completion_interruptible_timeout(&host->intr_wait,
+ host->timeout);
+ if (time <= 0) {
cmd->error = sh_mmcif_error_manage(host);
return;
}
@@ -579,19 +558,14 @@
cmd->error = sh_mmcif_error_manage(host);
break;
}
- host->sd_error = 0;
- host->wait_int = 0;
+ host->sd_error = false;
return;
}
if (!(cmd->flags & MMC_RSP_PRESENT)) {
cmd->error = ret;
- host->wait_int = 0;
return;
}
- if (host->wait_int == 1) {
- sh_mmcif_get_response(host, cmd);
- host->wait_int = 0;
- }
+ sh_mmcif_get_response(host, cmd);
if (host->data) {
ret = sh_mmcif_data_trans(host, mrq, cmd->opcode);
if (ret < 0)
@@ -618,15 +592,13 @@
return;
}
- time = wait_event_interruptible_timeout(host->intr_wait,
- host->wait_int == 1 ||
- host->sd_error == 1, host->timeout);
- if (host->wait_int != 1 && (time == 0 || host->sd_error != 0)) {
+ time = wait_for_completion_interruptible_timeout(&host->intr_wait,
+ host->timeout);
+ if (time <= 0 || host->sd_error) {
cmd->error = sh_mmcif_error_manage(host);
return;
}
sh_mmcif_get_cmd12response(host, cmd);
- host->wait_int = 0;
cmd->error = 0;
}
@@ -712,7 +684,7 @@
static irqreturn_t sh_mmcif_intr(int irq, void *dev_id)
{
struct sh_mmcif_host *host = dev_id;
- u32 state = 0;
+ u32 state;
int err = 0;
state = sh_mmcif_readl(host->addr, MMCIF_CE_INT);
@@ -757,11 +729,13 @@
err = 1;
}
if (err) {
- host->sd_error = 1;
+ host->sd_error = true;
pr_debug("%s: int err state = %08x\n", DRIVER_NAME, state);
}
- host->wait_int = 1;
- wake_up(&host->intr_wait);
+ if (state & ~(INT_CMD12RBE | INT_CMD12CRE))
+ complete(&host->intr_wait);
+ else
+ dev_dbg(&host->pd->dev, "Unexpected IRQ 0x%x\n", state);
return IRQ_HANDLED;
}
@@ -819,7 +793,7 @@
host->clk = clk_get_rate(host->hclk);
host->pd = pdev;
- init_waitqueue_head(&host->intr_wait);
+ init_completion(&host->intr_wait);
mmc->ops = &sh_mmcif_ops;
mmc->f_max = host->clk;
@@ -880,20 +854,21 @@
struct sh_mmcif_host *host = platform_get_drvdata(pdev);
int irq[2];
+ mmc_remove_host(host->mmc);
+
+ if (host->addr)
+ iounmap(host->addr);
+
sh_mmcif_writel(host->addr, MMCIF_CE_INT_MASK, MASK_ALL);
irq[0] = platform_get_irq(pdev, 0);
irq[1] = platform_get_irq(pdev, 1);
- if (host->addr)
- iounmap(host->addr);
-
- platform_set_drvdata(pdev, NULL);
- mmc_remove_host(host->mmc);
-
free_irq(irq[0], host);
free_irq(irq[1], host);
+ platform_set_drvdata(pdev, NULL);
+
clk_disable(host->hclk);
mmc_free_host(host->mmc);
@@ -924,5 +899,5 @@
MODULE_DESCRIPTION("SuperH on-chip MMC/eMMC interface driver");
MODULE_LICENSE("GPL");
-MODULE_ALIAS(DRIVER_NAME);
+MODULE_ALIAS("platform:" DRIVER_NAME);
MODULE_AUTHOR("Yusuke Goda <yusuke.goda.sx@renesas.com>");