* [PATCH] nand: Fix S3C NAND clock stop
@ 2011-04-11 1:27 Jiri Pinkava
2011-04-11 2:05 ` Randy Dunlap
0 siblings, 1 reply; 9+ messages in thread
From: Jiri Pinkava @ 2011-04-11 1:27 UTC (permalink / raw)
To: ben-linux
Cc: kgene.kim, dwmw2, linux-arm-kernel, linux-mtd, linux-kernel,
Jiri Pinkava
Current implementation of s3c2410_nand_select_chip call
clk_disable every time when chip = -1 (de-select). This happend
multiple times even if chip was already de-selected. This causes
disabling clock even if they are already disabled and due to
nature of clock subsytem implementation this causes nand clock
to be disabled and newer enabled again.
Signed-off-by: Jiri Pinkava <jiri.pinkava@vscht.cz>
---
drivers/mtd/nand/s3c2410.c | 57 +++++++++++++++++++++++++++++++------------
1 files changed, 41 insertions(+), 16 deletions(-)
diff --git a/drivers/mtd/nand/s3c2410.c b/drivers/mtd/nand/s3c2410.c
index 33d832d..79e18a3 100644
--- a/drivers/mtd/nand/s3c2410.c
+++ b/drivers/mtd/nand/s3c2410.c
@@ -54,8 +54,14 @@ static int hardware_ecc = 1;
static int hardware_ecc = 0;
#endif
+#define CLOCK_DISABLE 0
+#define CLOCK_ENABLE 1
+#define CLOCK_SUSPEND 2
+
+static int clock_state = CLOCK_DISABLE;
+
#ifdef CONFIG_MTD_NAND_S3C2410_CLKSTOP
-static int clock_stop = 1;
+static const int clock_stop = 1;
#else
static const int clock_stop = 0;
#endif
@@ -159,11 +165,33 @@ static struct s3c2410_platform_nand *to_nand_plat(struct platform_device *dev)
return dev->dev.platform_data;
}
-static inline int allow_clk_stop(struct s3c2410_nand_info *info)
+static inline int allow_clk_suspend(struct s3c2410_nand_info *info)
{
return clock_stop;
}
+/**
+ * s3c2410_nand_clk_set_state - Enable, disable or suspend NAND clock.
+ * @info: The controller instance.
+ * @state: State to which clock should be set.
+ */
+static void s3c2410_nand_clk_set_state(struct s3c2410_nand_info *info,
+ int new_state)
+{
+ if (!allow_clk_suspend(info) && new_state == CLOCK_SUSPEND)
+ return;
+
+ if (clock_state == CLOCK_ENABLE) {
+ if (new_state != CLOCK_ENABLE)
+ clk_disable(info->clk);
+ } else {
+ if (new_state == CLOCK_ENABLE)
+ clk_enable(info->clk);
+ }
+
+ clock_state = new_state;
+}
+
/* timing calculations */
#define NS_IN_KHZ 1000000
@@ -333,8 +361,8 @@ static void s3c2410_nand_select_chip(struct mtd_info *mtd, int chip)
nmtd = this->priv;
info = nmtd->info;
- if (chip != -1 && allow_clk_stop(info))
- clk_enable(info->clk);
+ if (chip != -1)
+ s3c2410_nand_clk_set_state(info, CLOCK_ENABLE);
cur = readl(info->sel_reg);
@@ -356,8 +384,8 @@ static void s3c2410_nand_select_chip(struct mtd_info *mtd, int chip)
writel(cur, info->sel_reg);
- if (chip == -1 && allow_clk_stop(info))
- clk_disable(info->clk);
+ if (chip == -1)
+ s3c2410_nand_clk_set_state(info, CLOCK_SUSPEND);
}
/* s3c2410_nand_hwcontrol
@@ -694,8 +722,7 @@ static int s3c24xx_nand_remove(struct platform_device *pdev)
/* free the common resources */
if (info->clk != NULL && !IS_ERR(info->clk)) {
- if (!allow_clk_stop(info))
- clk_disable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_DISABLE);
clk_put(info->clk);
}
@@ -947,7 +974,7 @@ static int s3c24xx_nand_probe(struct platform_device *pdev)
goto exit_error;
}
- clk_enable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_ENABLE);
/* allocate and map the resource */
@@ -1026,9 +1053,9 @@ static int s3c24xx_nand_probe(struct platform_device *pdev)
goto exit_error;
}
- if (allow_clk_stop(info)) {
+ if (allow_clk_suspend(info)) {
dev_info(&pdev->dev, "clock idle support enabled\n");
- clk_disable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_SUSPEND);
}
pr_debug("initialised ok\n");
@@ -1059,8 +1086,7 @@ static int s3c24xx_nand_suspend(struct platform_device *dev, pm_message_t pm)
writel(info->save_sel | info->sel_bit, info->sel_reg);
- if (!allow_clk_stop(info))
- clk_disable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_DISABLE);
}
return 0;
@@ -1072,7 +1098,7 @@ static int s3c24xx_nand_resume(struct platform_device *dev)
unsigned long sel;
if (info) {
- clk_enable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_ENABLE);
s3c2410_nand_inithw(info);
/* Restore the state of the nFCE line. */
@@ -1082,8 +1108,7 @@ static int s3c24xx_nand_resume(struct platform_device *dev)
sel |= info->save_sel & info->sel_bit;
writel(sel, info->sel_reg);
- if (allow_clk_stop(info))
- clk_disable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_SUSPEND);
}
return 0;
--
1.7.4.4
^ permalink raw reply related [flat|nested] 9+ messages in thread
* Re: [PATCH] nand: Fix S3C NAND clock stop
2011-04-11 1:27 [PATCH] nand: Fix S3C NAND clock stop Jiri Pinkava
@ 2011-04-11 2:05 ` Randy Dunlap
2011-04-11 3:15 ` Jiří Pinkava
0 siblings, 1 reply; 9+ messages in thread
From: Randy Dunlap @ 2011-04-11 2:05 UTC (permalink / raw)
To: Jiri Pinkava
Cc: ben-linux, kgene.kim, dwmw2, linux-arm-kernel, linux-mtd,
linux-kernel
On 4/10/2011 6:27 PM, Jiri Pinkava wrote:
> Current implementation of s3c2410_nand_select_chip call
> clk_disable every time when chip = -1 (de-select). This happend
> multiple times even if chip was already de-selected. This causes
> disabling clock even if they are already disabled and due to
> nature of clock subsytem implementation this causes nand clock
> to be disabled and newer enabled again.
>
> Signed-off-by: Jiri Pinkava<jiri.pinkava@vscht.cz>
> ---
> drivers/mtd/nand/s3c2410.c | 57 +++++++++++++++++++++++++++++++------------
> 1 files changed, 41 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/mtd/nand/s3c2410.c b/drivers/mtd/nand/s3c2410.c
> index 33d832d..79e18a3 100644
> --- a/drivers/mtd/nand/s3c2410.c
> +++ b/drivers/mtd/nand/s3c2410.c
> @@ -159,11 +165,33 @@ static struct s3c2410_platform_nand *to_nand_plat(struct platform_device *dev)
> return dev->dev.platform_data;
> }
>
> -static inline int allow_clk_stop(struct s3c2410_nand_info *info)
> +static inline int allow_clk_suspend(struct s3c2410_nand_info *info)
> {
> return clock_stop;
> }
>
> +/**
> + * s3c2410_nand_clk_set_state - Enable, disable or suspend NAND clock.
> + * @info: The controller instance.
> + * @state: State to which clock should be set.
@new_state:
> + */
> +static void s3c2410_nand_clk_set_state(struct s3c2410_nand_info *info,
> + int new_state)
> +{
> + if (!allow_clk_suspend(info)&& new_state == CLOCK_SUSPEND)
> + return;
> +
> + if (clock_state == CLOCK_ENABLE) {
> + if (new_state != CLOCK_ENABLE)
> + clk_disable(info->clk);
> + } else {
> + if (new_state == CLOCK_ENABLE)
> + clk_enable(info->clk);
> + }
> +
> + clock_state = new_state;
> +}
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] nand: Fix S3C NAND clock stop
2011-04-11 2:05 ` Randy Dunlap
@ 2011-04-11 3:15 ` Jiří Pinkava
2011-04-11 14:48 ` Jiri Pinkava
0 siblings, 1 reply; 9+ messages in thread
From: Jiří Pinkava @ 2011-04-11 3:15 UTC (permalink / raw)
To: Randy Dunlap
Cc: ben-linux@fluff.org, kgene.kim@samsung.com, dwmw2@infradead.org,
linux-arm-kernel@lists.infradead.org,
linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org
[-- Attachment #1: Type: text/plain, Size: 4329 bytes --]
Current implementation of s3c2410_nand_select_chip call
clk_disable every time when chip = -1 (de-select). This happend
multiple times even if chip was already de-selected. This causes
disabling clock even if they are already disabled and due to
nature of clock subsytem implementation this causes nand clock
to be disabled and newer enabled again.
Signed-off-by: Jiri Pinkava <jiri.pinkava@vscht.cz>
---
drivers/mtd/nand/s3c2410.c | 57
+++++++++++++++++++++++++++++++------------
1 files changed, 41 insertions(+), 16 deletions(-)
diff --git a/drivers/mtd/nand/s3c2410.c b/drivers/mtd/nand/s3c2410.c
index 33d832d..fbc37dc 100644
--- a/drivers/mtd/nand/s3c2410.c
+++ b/drivers/mtd/nand/s3c2410.c
@@ -54,8 +54,14 @@ static int hardware_ecc = 1;
static int hardware_ecc = 0;
#endif
+#define CLOCK_DISABLE 0
+#define CLOCK_ENABLE 1
+#define CLOCK_SUSPEND 2
+
+static int clock_state = CLOCK_DISABLE;
+
#ifdef CONFIG_MTD_NAND_S3C2410_CLKSTOP
-static int clock_stop = 1;
+static const int clock_stop = 1;
#else
static const int clock_stop = 0;
#endif
@@ -159,11 +165,33 @@ static struct s3c2410_platform_nand
*to_nand_plat(struct platform_device *dev)
return dev->dev.platform_data;
}
-static inline int allow_clk_stop(struct s3c2410_nand_info *info)
+static inline int allow_clk_suspend(struct s3c2410_nand_info *info)
{
return clock_stop;
}
+/**
+ * s3c2410_nand_clk_set_state - Enable, disable or suspend NAND clock.
+ * @info: The controller instance.
+ * @new_state: State to which clock should be set.
+ */
+static void s3c2410_nand_clk_set_state(struct s3c2410_nand_info *info,
+ int new_state)
+{
+ if (!allow_clk_suspend(info) && new_state == CLOCK_SUSPEND)
+ return;
+
+ if (clock_state == CLOCK_ENABLE) {
+ if (new_state != CLOCK_ENABLE)
+ clk_disable(info->clk);
+ } else {
+ if (new_state == CLOCK_ENABLE)
+ clk_enable(info->clk);
+ }
+
+ clock_state = new_state;
+}
+
/* timing calculations */
#define NS_IN_KHZ 1000000
@@ -333,8 +361,8 @@ static void s3c2410_nand_select_chip(struct mtd_info
*mtd, int chip)
nmtd = this->priv;
info = nmtd->info;
- if (chip != -1 && allow_clk_stop(info))
- clk_enable(info->clk);
+ if (chip != -1)
+ s3c2410_nand_clk_set_state(info, CLOCK_ENABLE);
cur = readl(info->sel_reg);
@@ -356,8 +384,8 @@ static void s3c2410_nand_select_chip(struct mtd_info
*mtd, int chip)
writel(cur, info->sel_reg);
- if (chip == -1 && allow_clk_stop(info))
- clk_disable(info->clk);
+ if (chip == -1)
+ s3c2410_nand_clk_set_state(info, CLOCK_SUSPEND);
}
/* s3c2410_nand_hwcontrol
@@ -694,8 +722,7 @@ static int s3c24xx_nand_remove(struct
platform_device *pdev)
/* free the common resources */
if (info->clk != NULL && !IS_ERR(info->clk)) {
- if (!allow_clk_stop(info))
- clk_disable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_DISABLE);
clk_put(info->clk);
}
@@ -947,7 +974,7 @@ static int s3c24xx_nand_probe(struct platform_device
*pdev)
goto exit_error;
}
- clk_enable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_ENABLE);
/* allocate and map the resource */
@@ -1026,9 +1053,9 @@ static int s3c24xx_nand_probe(struct
platform_device *pdev)
goto exit_error;
}
- if (allow_clk_stop(info)) {
+ if (allow_clk_suspend(info)) {
dev_info(&pdev->dev, "clock idle support enabled\n");
- clk_disable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_SUSPEND);
}
pr_debug("initialised ok\n");
@@ -1059,8 +1086,7 @@ static int s3c24xx_nand_suspend(struct
platform_device *dev, pm_message_t pm)
writel(info->save_sel | info->sel_bit, info->sel_reg);
- if (!allow_clk_stop(info))
- clk_disable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_DISABLE);
}
return 0;
@@ -1072,7 +1098,7 @@ static int s3c24xx_nand_resume(struct
platform_device *dev)
unsigned long sel;
if (info) {
- clk_enable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_ENABLE);
s3c2410_nand_inithw(info);
/* Restore the state of the nFCE line. */
@@ -1082,8 +1108,7 @@ static int s3c24xx_nand_resume(struct
platform_device *dev)
sel |= info->save_sel & info->sel_bit;
writel(sel, info->sel_reg);
- if (allow_clk_stop(info))
- clk_disable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_SUSPEND);
}
return 0;
--
1.7.4.4
[-- Attachment #2: 0001-nand-Fix-S3C-NAND-clock-stop.patch --]
[-- Type: text/x-patch, Size: 4499 bytes --]
>From 4fd7086f28d6452f1edafa903e7becd5a0f017c6 Mon Sep 17 00:00:00 2001
From: Jiri Pinkava <jiri.pinkava@vscht.cz>
Date: Mon, 11 Apr 2011 03:20:33 +0200
Subject: [PATCH] nand: Fix S3C NAND clock stop
Current implementation of s3c2410_nand_select_chip call
clk_disable every time when chip = -1 (de-select). This happend
multiple times even if chip was already de-selected. This causes
disabling clock even if they are already disabled and due to
nature of clock subsytem implementation this causes nand clock
to be disabled and newer enabled again.
Signed-off-by: Jiri Pinkava <jiri.pinkava@vscht.cz>
---
drivers/mtd/nand/s3c2410.c | 57 +++++++++++++++++++++++++++++++------------
1 files changed, 41 insertions(+), 16 deletions(-)
diff --git a/drivers/mtd/nand/s3c2410.c b/drivers/mtd/nand/s3c2410.c
index 33d832d..fbc37dc 100644
--- a/drivers/mtd/nand/s3c2410.c
+++ b/drivers/mtd/nand/s3c2410.c
@@ -54,8 +54,14 @@ static int hardware_ecc = 1;
static int hardware_ecc = 0;
#endif
+#define CLOCK_DISABLE 0
+#define CLOCK_ENABLE 1
+#define CLOCK_SUSPEND 2
+
+static int clock_state = CLOCK_DISABLE;
+
#ifdef CONFIG_MTD_NAND_S3C2410_CLKSTOP
-static int clock_stop = 1;
+static const int clock_stop = 1;
#else
static const int clock_stop = 0;
#endif
@@ -159,11 +165,33 @@ static struct s3c2410_platform_nand *to_nand_plat(struct platform_device *dev)
return dev->dev.platform_data;
}
-static inline int allow_clk_stop(struct s3c2410_nand_info *info)
+static inline int allow_clk_suspend(struct s3c2410_nand_info *info)
{
return clock_stop;
}
+/**
+ * s3c2410_nand_clk_set_state - Enable, disable or suspend NAND clock.
+ * @info: The controller instance.
+ * @new_state: State to which clock should be set.
+ */
+static void s3c2410_nand_clk_set_state(struct s3c2410_nand_info *info,
+ int new_state)
+{
+ if (!allow_clk_suspend(info) && new_state == CLOCK_SUSPEND)
+ return;
+
+ if (clock_state == CLOCK_ENABLE) {
+ if (new_state != CLOCK_ENABLE)
+ clk_disable(info->clk);
+ } else {
+ if (new_state == CLOCK_ENABLE)
+ clk_enable(info->clk);
+ }
+
+ clock_state = new_state;
+}
+
/* timing calculations */
#define NS_IN_KHZ 1000000
@@ -333,8 +361,8 @@ static void s3c2410_nand_select_chip(struct mtd_info *mtd, int chip)
nmtd = this->priv;
info = nmtd->info;
- if (chip != -1 && allow_clk_stop(info))
- clk_enable(info->clk);
+ if (chip != -1)
+ s3c2410_nand_clk_set_state(info, CLOCK_ENABLE);
cur = readl(info->sel_reg);
@@ -356,8 +384,8 @@ static void s3c2410_nand_select_chip(struct mtd_info *mtd, int chip)
writel(cur, info->sel_reg);
- if (chip == -1 && allow_clk_stop(info))
- clk_disable(info->clk);
+ if (chip == -1)
+ s3c2410_nand_clk_set_state(info, CLOCK_SUSPEND);
}
/* s3c2410_nand_hwcontrol
@@ -694,8 +722,7 @@ static int s3c24xx_nand_remove(struct platform_device *pdev)
/* free the common resources */
if (info->clk != NULL && !IS_ERR(info->clk)) {
- if (!allow_clk_stop(info))
- clk_disable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_DISABLE);
clk_put(info->clk);
}
@@ -947,7 +974,7 @@ static int s3c24xx_nand_probe(struct platform_device *pdev)
goto exit_error;
}
- clk_enable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_ENABLE);
/* allocate and map the resource */
@@ -1026,9 +1053,9 @@ static int s3c24xx_nand_probe(struct platform_device *pdev)
goto exit_error;
}
- if (allow_clk_stop(info)) {
+ if (allow_clk_suspend(info)) {
dev_info(&pdev->dev, "clock idle support enabled\n");
- clk_disable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_SUSPEND);
}
pr_debug("initialised ok\n");
@@ -1059,8 +1086,7 @@ static int s3c24xx_nand_suspend(struct platform_device *dev, pm_message_t pm)
writel(info->save_sel | info->sel_bit, info->sel_reg);
- if (!allow_clk_stop(info))
- clk_disable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_DISABLE);
}
return 0;
@@ -1072,7 +1098,7 @@ static int s3c24xx_nand_resume(struct platform_device *dev)
unsigned long sel;
if (info) {
- clk_enable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_ENABLE);
s3c2410_nand_inithw(info);
/* Restore the state of the nFCE line. */
@@ -1082,8 +1108,7 @@ static int s3c24xx_nand_resume(struct platform_device *dev)
sel |= info->save_sel & info->sel_bit;
writel(sel, info->sel_reg);
- if (allow_clk_stop(info))
- clk_disable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_SUSPEND);
}
return 0;
--
1.7.4.4
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH] nand: Fix S3C NAND clock stop
2011-04-11 3:15 ` Jiří Pinkava
@ 2011-04-11 14:48 ` Jiri Pinkava
2011-04-13 3:36 ` Artem Bityutskiy
0 siblings, 1 reply; 9+ messages in thread
From: Jiri Pinkava @ 2011-04-11 14:48 UTC (permalink / raw)
To: dedekind1; +Cc: ben-linux, linux-kernel, linux-mtd, Jiri Pinkava
Current implementation of s3c2410_nand_select_chip call
clk_disable every time when chip = -1 (de-select). This happend
multiple times even if chip was already de-selected. This causes
disabling clock even if they are already disabled and due to
nature of clock subsytem implementation this causes nand clock
to be disabled and newer enabled again.
Signed-off-by: Jiri Pinkava <jiri.pinkava@vscht.cz>
---
drivers/mtd/nand/s3c2410.c | 59 ++++++++++++++++++++++++++++++++------------
1 files changed, 43 insertions(+), 16 deletions(-)
diff --git a/drivers/mtd/nand/s3c2410.c b/drivers/mtd/nand/s3c2410.c
index 33d832d..cea775a 100644
--- a/drivers/mtd/nand/s3c2410.c
+++ b/drivers/mtd/nand/s3c2410.c
@@ -55,7 +55,7 @@ static int hardware_ecc = 0;
#endif
#ifdef CONFIG_MTD_NAND_S3C2410_CLKSTOP
-static int clock_stop = 1;
+static const int clock_stop = 1;
#else
static const int clock_stop = 0;
#endif
@@ -96,6 +96,12 @@ enum s3c_cpu_type {
TYPE_S3C2440,
};
+enum s3c_nand_clk_state {
+ CLOCK_DISABLE = 0,
+ CLOCK_ENABLE,
+ CLOCK_SUSPEND,
+};
+
/* overview of the s3c2410 nand state */
/**
@@ -111,6 +117,7 @@ enum s3c_cpu_type {
* @mtd_count: The number of MTDs created from this controller.
* @save_sel: The contents of @sel_reg to be saved over suspend.
* @clk_rate: The clock rate from @clk.
+ * @clk_state: The current clock state.
* @cpu_type: The exact type of this controller.
*/
struct s3c2410_nand_info {
@@ -129,6 +136,7 @@ struct s3c2410_nand_info {
int mtd_count;
unsigned long save_sel;
unsigned long clk_rate;
+ enum s3c_nand_clk_state clk_state;
enum s3c_cpu_type cpu_type;
@@ -159,11 +167,33 @@ static struct s3c2410_platform_nand *to_nand_plat(struct platform_device *dev)
return dev->dev.platform_data;
}
-static inline int allow_clk_stop(struct s3c2410_nand_info *info)
+static inline int allow_clk_suspend(struct s3c2410_nand_info *info)
{
return clock_stop;
}
+/**
+ * s3c2410_nand_clk_set_state - Enable, disable or suspend NAND clock.
+ * @info: The controller instance.
+ * @new_state: State to which clock should be set.
+ */
+static void s3c2410_nand_clk_set_state(struct s3c2410_nand_info *info,
+ enum s3c_nand_clk_state new_state)
+{
+ if (!allow_clk_suspend(info) && new_state == CLOCK_SUSPEND)
+ return;
+
+ if (info->clk_state == CLOCK_ENABLE) {
+ if (new_state != CLOCK_ENABLE)
+ clk_disable(info->clk);
+ } else {
+ if (new_state == CLOCK_ENABLE)
+ clk_enable(info->clk);
+ }
+
+ info->clk_state = new_state;
+}
+
/* timing calculations */
#define NS_IN_KHZ 1000000
@@ -333,8 +363,8 @@ static void s3c2410_nand_select_chip(struct mtd_info *mtd, int chip)
nmtd = this->priv;
info = nmtd->info;
- if (chip != -1 && allow_clk_stop(info))
- clk_enable(info->clk);
+ if (chip != -1)
+ s3c2410_nand_clk_set_state(info, CLOCK_ENABLE);
cur = readl(info->sel_reg);
@@ -356,8 +386,8 @@ static void s3c2410_nand_select_chip(struct mtd_info *mtd, int chip)
writel(cur, info->sel_reg);
- if (chip == -1 && allow_clk_stop(info))
- clk_disable(info->clk);
+ if (chip == -1)
+ s3c2410_nand_clk_set_state(info, CLOCK_SUSPEND);
}
/* s3c2410_nand_hwcontrol
@@ -694,8 +724,7 @@ static int s3c24xx_nand_remove(struct platform_device *pdev)
/* free the common resources */
if (info->clk != NULL && !IS_ERR(info->clk)) {
- if (!allow_clk_stop(info))
- clk_disable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_DISABLE);
clk_put(info->clk);
}
@@ -947,7 +976,7 @@ static int s3c24xx_nand_probe(struct platform_device *pdev)
goto exit_error;
}
- clk_enable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_ENABLE);
/* allocate and map the resource */
@@ -1026,9 +1055,9 @@ static int s3c24xx_nand_probe(struct platform_device *pdev)
goto exit_error;
}
- if (allow_clk_stop(info)) {
+ if (allow_clk_suspend(info)) {
dev_info(&pdev->dev, "clock idle support enabled\n");
- clk_disable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_SUSPEND);
}
pr_debug("initialised ok\n");
@@ -1059,8 +1088,7 @@ static int s3c24xx_nand_suspend(struct platform_device *dev, pm_message_t pm)
writel(info->save_sel | info->sel_bit, info->sel_reg);
- if (!allow_clk_stop(info))
- clk_disable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_DISABLE);
}
return 0;
@@ -1072,7 +1100,7 @@ static int s3c24xx_nand_resume(struct platform_device *dev)
unsigned long sel;
if (info) {
- clk_enable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_ENABLE);
s3c2410_nand_inithw(info);
/* Restore the state of the nFCE line. */
@@ -1082,8 +1110,7 @@ static int s3c24xx_nand_resume(struct platform_device *dev)
sel |= info->save_sel & info->sel_bit;
writel(sel, info->sel_reg);
- if (allow_clk_stop(info))
- clk_disable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_SUSPEND);
}
return 0;
--
1.7.4.4
^ permalink raw reply related [flat|nested] 9+ messages in thread
* Re: [PATCH] nand: Fix S3C NAND clock stop
2011-04-11 14:48 ` Jiri Pinkava
@ 2011-04-13 3:36 ` Artem Bityutskiy
2011-04-13 9:59 ` [PATCH 1/2] " Jiri Pinkava
0 siblings, 1 reply; 9+ messages in thread
From: Artem Bityutskiy @ 2011-04-13 3:36 UTC (permalink / raw)
To: Jiri Pinkava; +Cc: ben-linux, linux-kernel, linux-mtd
On Mon, 2011-04-11 at 16:48 +0200, Jiri Pinkava wrote:
> Current implementation of s3c2410_nand_select_chip call
> clk_disable every time when chip = -1 (de-select). This happend
> multiple times even if chip was already de-selected. This causes
> disabling clock even if they are already disabled and due to
> nature of clock subsytem implementation this causes nand clock
> to be disabled and newer enabled again.
>
> Signed-off-by: Jiri Pinkava <jiri.pinkava@vscht.cz>
> ---
> drivers/mtd/nand/s3c2410.c | 59 ++++++++++++++++++++++++++++++++------------
> 1 files changed, 43 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/mtd/nand/s3c2410.c b/drivers/mtd/nand/s3c2410.c
> index 33d832d..cea775a 100644
> --- a/drivers/mtd/nand/s3c2410.c
> +++ b/drivers/mtd/nand/s3c2410.c
> @@ -55,7 +55,7 @@ static int hardware_ecc = 0;
> #endif
>
> #ifdef CONFIG_MTD_NAND_S3C2410_CLKSTOP
> -static int clock_stop = 1;
> +static const int clock_stop = 1;
> #else
> static const int clock_stop = 0;
> #endif
Please, kill clock_stop variable completely in a separate patch.
--
Best Regards,
Artem Bityutskiy (Битюцкий Артём)
^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH 1/2] nand: Fix S3C NAND clock stop
2011-04-13 3:36 ` Artem Bityutskiy
@ 2011-04-13 9:59 ` Jiri Pinkava
2011-04-13 9:59 ` [PATCH 2/2] nand: Remove unnecessary variable Jiri Pinkava
2011-04-14 12:16 ` [PATCH 1/2] nand: Fix S3C NAND clock stop Artem Bityutskiy
0 siblings, 2 replies; 9+ messages in thread
From: Jiri Pinkava @ 2011-04-13 9:59 UTC (permalink / raw)
To: dedekind1; +Cc: ben-linux, linux-kernel, linux-mtd, Jiri Pinkava
Current implementation of s3c2410_nand_select_chip call
clk_disable every time when chip = -1 (de-select). This happend
multiple times even if chip was already de-selected. This causes
disabling clock even if they are already disabled and due to
nature of clock subsytem implementation this causes nand clock
to be disabled and newer enabled again.
Signed-off-by: Jiri Pinkava <jiri.pinkava@vscht.cz>
---
drivers/mtd/nand/s3c2410.c | 59 ++++++++++++++++++++++++++++++++------------
1 files changed, 43 insertions(+), 16 deletions(-)
diff --git a/drivers/mtd/nand/s3c2410.c b/drivers/mtd/nand/s3c2410.c
index 33d832d..cea775a 100644
--- a/drivers/mtd/nand/s3c2410.c
+++ b/drivers/mtd/nand/s3c2410.c
@@ -55,7 +55,7 @@ static int hardware_ecc = 0;
#endif
#ifdef CONFIG_MTD_NAND_S3C2410_CLKSTOP
-static int clock_stop = 1;
+static const int clock_stop = 1;
#else
static const int clock_stop = 0;
#endif
@@ -96,6 +96,12 @@ enum s3c_cpu_type {
TYPE_S3C2440,
};
+enum s3c_nand_clk_state {
+ CLOCK_DISABLE = 0,
+ CLOCK_ENABLE,
+ CLOCK_SUSPEND,
+};
+
/* overview of the s3c2410 nand state */
/**
@@ -111,6 +117,7 @@ enum s3c_cpu_type {
* @mtd_count: The number of MTDs created from this controller.
* @save_sel: The contents of @sel_reg to be saved over suspend.
* @clk_rate: The clock rate from @clk.
+ * @clk_state: The current clock state.
* @cpu_type: The exact type of this controller.
*/
struct s3c2410_nand_info {
@@ -129,6 +136,7 @@ struct s3c2410_nand_info {
int mtd_count;
unsigned long save_sel;
unsigned long clk_rate;
+ enum s3c_nand_clk_state clk_state;
enum s3c_cpu_type cpu_type;
@@ -159,11 +167,33 @@ static struct s3c2410_platform_nand *to_nand_plat(struct platform_device *dev)
return dev->dev.platform_data;
}
-static inline int allow_clk_stop(struct s3c2410_nand_info *info)
+static inline int allow_clk_suspend(struct s3c2410_nand_info *info)
{
return clock_stop;
}
+/**
+ * s3c2410_nand_clk_set_state - Enable, disable or suspend NAND clock.
+ * @info: The controller instance.
+ * @new_state: State to which clock should be set.
+ */
+static void s3c2410_nand_clk_set_state(struct s3c2410_nand_info *info,
+ enum s3c_nand_clk_state new_state)
+{
+ if (!allow_clk_suspend(info) && new_state == CLOCK_SUSPEND)
+ return;
+
+ if (info->clk_state == CLOCK_ENABLE) {
+ if (new_state != CLOCK_ENABLE)
+ clk_disable(info->clk);
+ } else {
+ if (new_state == CLOCK_ENABLE)
+ clk_enable(info->clk);
+ }
+
+ info->clk_state = new_state;
+}
+
/* timing calculations */
#define NS_IN_KHZ 1000000
@@ -333,8 +363,8 @@ static void s3c2410_nand_select_chip(struct mtd_info *mtd, int chip)
nmtd = this->priv;
info = nmtd->info;
- if (chip != -1 && allow_clk_stop(info))
- clk_enable(info->clk);
+ if (chip != -1)
+ s3c2410_nand_clk_set_state(info, CLOCK_ENABLE);
cur = readl(info->sel_reg);
@@ -356,8 +386,8 @@ static void s3c2410_nand_select_chip(struct mtd_info *mtd, int chip)
writel(cur, info->sel_reg);
- if (chip == -1 && allow_clk_stop(info))
- clk_disable(info->clk);
+ if (chip == -1)
+ s3c2410_nand_clk_set_state(info, CLOCK_SUSPEND);
}
/* s3c2410_nand_hwcontrol
@@ -694,8 +724,7 @@ static int s3c24xx_nand_remove(struct platform_device *pdev)
/* free the common resources */
if (info->clk != NULL && !IS_ERR(info->clk)) {
- if (!allow_clk_stop(info))
- clk_disable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_DISABLE);
clk_put(info->clk);
}
@@ -947,7 +976,7 @@ static int s3c24xx_nand_probe(struct platform_device *pdev)
goto exit_error;
}
- clk_enable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_ENABLE);
/* allocate and map the resource */
@@ -1026,9 +1055,9 @@ static int s3c24xx_nand_probe(struct platform_device *pdev)
goto exit_error;
}
- if (allow_clk_stop(info)) {
+ if (allow_clk_suspend(info)) {
dev_info(&pdev->dev, "clock idle support enabled\n");
- clk_disable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_SUSPEND);
}
pr_debug("initialised ok\n");
@@ -1059,8 +1088,7 @@ static int s3c24xx_nand_suspend(struct platform_device *dev, pm_message_t pm)
writel(info->save_sel | info->sel_bit, info->sel_reg);
- if (!allow_clk_stop(info))
- clk_disable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_DISABLE);
}
return 0;
@@ -1072,7 +1100,7 @@ static int s3c24xx_nand_resume(struct platform_device *dev)
unsigned long sel;
if (info) {
- clk_enable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_ENABLE);
s3c2410_nand_inithw(info);
/* Restore the state of the nFCE line. */
@@ -1082,8 +1110,7 @@ static int s3c24xx_nand_resume(struct platform_device *dev)
sel |= info->save_sel & info->sel_bit;
writel(sel, info->sel_reg);
- if (allow_clk_stop(info))
- clk_disable(info->clk);
+ s3c2410_nand_clk_set_state(info, CLOCK_SUSPEND);
}
return 0;
--
1.7.4.4
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH 2/2] nand: Remove unnecessary variable
2011-04-13 9:59 ` [PATCH 1/2] " Jiri Pinkava
@ 2011-04-13 9:59 ` Jiri Pinkava
2011-04-14 12:17 ` Artem Bityutskiy
2011-04-14 12:16 ` [PATCH 1/2] nand: Fix S3C NAND clock stop Artem Bityutskiy
1 sibling, 1 reply; 9+ messages in thread
From: Jiri Pinkava @ 2011-04-13 9:59 UTC (permalink / raw)
To: dedekind1; +Cc: ben-linux, linux-kernel, linux-mtd, Jiri Pinkava
Signed-off-by: Jiri Pinkava <jiri.pinkava@vscht.cz>
---
drivers/mtd/nand/s3c2410.c | 12 +++++-------
1 files changed, 5 insertions(+), 7 deletions(-)
diff --git a/drivers/mtd/nand/s3c2410.c b/drivers/mtd/nand/s3c2410.c
index cea775a..8041038 100644
--- a/drivers/mtd/nand/s3c2410.c
+++ b/drivers/mtd/nand/s3c2410.c
@@ -54,12 +54,6 @@ static int hardware_ecc = 1;
static int hardware_ecc = 0;
#endif
-#ifdef CONFIG_MTD_NAND_S3C2410_CLKSTOP
-static const int clock_stop = 1;
-#else
-static const int clock_stop = 0;
-#endif
-
/* new oob placement block for use with hardware ecc generation
*/
@@ -169,7 +163,11 @@ static struct s3c2410_platform_nand *to_nand_plat(struct platform_device *dev)
static inline int allow_clk_suspend(struct s3c2410_nand_info *info)
{
- return clock_stop;
+#ifdef CONFIG_MTD_NAND_S3C2410_CLKSTOP
+ return 1;
+#else
+ return 0;
+#endif
}
/**
--
1.7.4.4
^ permalink raw reply related [flat|nested] 9+ messages in thread
* Re: [PATCH 1/2] nand: Fix S3C NAND clock stop
2011-04-13 9:59 ` [PATCH 1/2] " Jiri Pinkava
2011-04-13 9:59 ` [PATCH 2/2] nand: Remove unnecessary variable Jiri Pinkava
@ 2011-04-14 12:16 ` Artem Bityutskiy
1 sibling, 0 replies; 9+ messages in thread
From: Artem Bityutskiy @ 2011-04-14 12:16 UTC (permalink / raw)
To: Jiri Pinkava; +Cc: ben-linux, linux-kernel, linux-mtd
On Wed, 2011-04-13 at 11:59 +0200, Jiri Pinkava wrote:
> Current implementation of s3c2410_nand_select_chip call
> clk_disable every time when chip = -1 (de-select). This happend
> multiple times even if chip was already de-selected. This causes
> disabling clock even if they are already disabled and due to
> nature of clock subsytem implementation this causes nand clock
> to be disabled and newer enabled again.
>
> Signed-off-by: Jiri Pinkava <jiri.pinkava@vscht.cz>
Pushed to l2-mtd-2.6.git, thanks.
--
Best Regards,
Artem Bityutskiy (Артём Битюцкий)
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH 2/2] nand: Remove unnecessary variable
2011-04-13 9:59 ` [PATCH 2/2] nand: Remove unnecessary variable Jiri Pinkava
@ 2011-04-14 12:17 ` Artem Bityutskiy
0 siblings, 0 replies; 9+ messages in thread
From: Artem Bityutskiy @ 2011-04-14 12:17 UTC (permalink / raw)
To: Jiri Pinkava; +Cc: ben-linux, linux-kernel, linux-mtd
On Wed, 2011-04-13 at 11:59 +0200, Jiri Pinkava wrote:
> Signed-off-by: Jiri Pinkava <jiri.pinkava@vscht.cz>
> ---
> drivers/mtd/nand/s3c2410.c | 12 +++++-------
> 1 files changed, 5 insertions(+), 7 deletions(-)
Let's drop this, sorry, I gave you wrong advise.
--
Best Regards,
Artem Bityutskiy (Артём Битюцкий)
^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2011-04-14 12:20 UTC | newest]
Thread overview: 9+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2011-04-11 1:27 [PATCH] nand: Fix S3C NAND clock stop Jiri Pinkava
2011-04-11 2:05 ` Randy Dunlap
2011-04-11 3:15 ` Jiří Pinkava
2011-04-11 14:48 ` Jiri Pinkava
2011-04-13 3:36 ` Artem Bityutskiy
2011-04-13 9:59 ` [PATCH 1/2] " Jiri Pinkava
2011-04-13 9:59 ` [PATCH 2/2] nand: Remove unnecessary variable Jiri Pinkava
2011-04-14 12:17 ` Artem Bityutskiy
2011-04-14 12:16 ` [PATCH 1/2] nand: Fix S3C NAND clock stop Artem Bityutskiy
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