* [PATCH v3 1/3] i2c/at91: add support for runtime PM
[not found] ` <1414133417-11530-1-git-send-email-wenyou.yang-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
@ 2014-10-24 6:50 ` Wenyou Yang
2014-11-08 18:03 ` Wolfram Sang
2014-10-24 6:50 ` [PATCH v3 2/3] i2c/at91: add support for system PM Wenyou Yang
` (2 subsequent siblings)
3 siblings, 1 reply; 12+ messages in thread
From: Wenyou Yang @ 2014-10-24 6:50 UTC (permalink / raw)
To: wsa-z923LK4zBo2bacvFa/9K2g,
ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w
Cc: linux-i2c-u79uwXL29TY76Z2rM5mHXA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA,
nicolas.ferre-AIFe0yeh4nAAvxtiuMwx3w,
khilman-DgEjT+Ai2ygdnm+yROfE0A,
linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r,
wenyou.yang-AIFe0yeh4nAAvxtiuMwx3w
Drivers should put the device into low power states proactively whenever the
device is not in use. Thus implement support for runtime PM and use the
autosuspend feature to make sure that we can still perform well in case we see
lots of i2c traffic within short period of time.
Signed-off-by: Wenyou Yang <wenyou.yang-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
---
drivers/i2c/busses/i2c-at91.c | 38 ++++++++++++++++++++++++++++++++------
1 file changed, 32 insertions(+), 6 deletions(-)
diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c
index 917d545..a25fb5e 100644
--- a/drivers/i2c/busses/i2c-at91.c
+++ b/drivers/i2c/busses/i2c-at91.c
@@ -31,10 +31,12 @@
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/platform_data/dma-atmel.h>
+#include <linux/pm_runtime.h>
#define DEFAULT_TWI_CLK_HZ 100000 /* max 400 Kbits/s */
#define AT91_I2C_TIMEOUT msecs_to_jiffies(100) /* transfer timeout */
#define AT91_I2C_DMA_THRESHOLD 8 /* enable DMA if transfer size is bigger than this threshold */
+#define AUTOSUSPEND_TIMEOUT 2000
/* AT91 TWI register definitions */
#define AT91_TWI_CR 0x0000 /* Control Register */
@@ -481,6 +483,10 @@ static int at91_twi_xfer(struct i2c_adapter *adap, struct i2c_msg *msg, int num)
dev_dbg(&adap->dev, "at91_xfer: processing %d messages:\n", num);
+ ret = pm_runtime_get_sync(dev->dev);
+ if (ret < 0)
+ goto out;
+
/*
* The hardware can handle at most two messages concatenated by a
* repeated start via it's internal address feature.
@@ -488,18 +494,21 @@ static int at91_twi_xfer(struct i2c_adapter *adap, struct i2c_msg *msg, int num)
if (num > 2) {
dev_err(dev->dev,
"cannot handle more than two concatenated messages.\n");
- return 0;
+ ret = 0;
+ goto out;
} else if (num == 2) {
int internal_address = 0;
int i;
if (msg->flags & I2C_M_RD) {
dev_err(dev->dev, "first transfer must be write.\n");
- return -EINVAL;
+ ret = -EINVAL;
+ goto out;
}
if (msg->len > 3) {
dev_err(dev->dev, "first message size must be <= 3.\n");
- return -EINVAL;
+ ret = -EINVAL;
+ goto out;
}
/* 1st msg is put into the internal address, start with 2nd */
@@ -523,7 +532,12 @@ static int at91_twi_xfer(struct i2c_adapter *adap, struct i2c_msg *msg, int num)
ret = at91_do_twi_transfer(dev);
- return (ret < 0) ? ret : num;
+ ret = (ret < 0) ? ret : num;
+out:
+ pm_runtime_mark_last_busy(dev->dev);
+ pm_runtime_put_autosuspend(dev->dev);
+
+ return ret;
}
static u32 at91_twi_func(struct i2c_adapter *adapter)
@@ -795,11 +809,20 @@ static int at91_twi_probe(struct platform_device *pdev)
dev->adapter.timeout = AT91_I2C_TIMEOUT;
dev->adapter.dev.of_node = pdev->dev.of_node;
+ pm_runtime_set_autosuspend_delay(dev->dev, AUTOSUSPEND_TIMEOUT);
+ pm_runtime_use_autosuspend(dev->dev);
+ pm_runtime_set_active(dev->dev);
+ pm_runtime_enable(dev->dev);
+
rc = i2c_add_numbered_adapter(&dev->adapter);
if (rc) {
dev_err(dev->dev, "Adapter %s registration failed\n",
dev->adapter.name);
clk_disable_unprepare(dev->clk);
+
+ pm_runtime_disable(dev->dev);
+ pm_runtime_set_suspended(dev->dev);
+
return rc;
}
@@ -814,6 +837,9 @@ static int at91_twi_remove(struct platform_device *pdev)
i2c_del_adapter(&dev->adapter);
clk_disable_unprepare(dev->clk);
+ pm_runtime_disable(dev->dev);
+ pm_runtime_set_suspended(dev->dev);
+
return 0;
}
@@ -823,7 +849,7 @@ static int at91_twi_runtime_suspend(struct device *dev)
{
struct at91_twi_dev *twi_dev = dev_get_drvdata(dev);
- clk_disable(twi_dev->clk);
+ clk_disable_unprepare(twi_dev->clk);
return 0;
}
@@ -832,7 +858,7 @@ static int at91_twi_runtime_resume(struct device *dev)
{
struct at91_twi_dev *twi_dev = dev_get_drvdata(dev);
- return clk_enable(twi_dev->clk);
+ return clk_prepare_enable(twi_dev->clk);
}
static const struct dev_pm_ops at91_twi_pm = {
--
1.7.9.5
^ permalink raw reply related [flat|nested] 12+ messages in thread* Re: [PATCH v3 1/3] i2c/at91: add support for runtime PM
2014-10-24 6:50 ` [PATCH v3 1/3] i2c/at91: add support for runtime PM Wenyou Yang
@ 2014-11-08 18:03 ` Wolfram Sang
0 siblings, 0 replies; 12+ messages in thread
From: Wolfram Sang @ 2014-11-08 18:03 UTC (permalink / raw)
To: Wenyou Yang
Cc: ludovic.desroches, linux-i2c, linux-kernel, nicolas.ferre,
khilman, linux-arm-kernel
[-- Attachment #1: Type: text/plain, Size: 443 bytes --]
On Fri, Oct 24, 2014 at 02:50:15PM +0800, Wenyou Yang wrote:
> Drivers should put the device into low power states proactively whenever the
> device is not in use. Thus implement support for runtime PM and use the
> autosuspend feature to make sure that we can still perform well in case we see
> lots of i2c traffic within short period of time.
>
> Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Applied to for-next, thanks!
[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 819 bytes --]
^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH v3 2/3] i2c/at91: add support for system PM
[not found] ` <1414133417-11530-1-git-send-email-wenyou.yang-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
2014-10-24 6:50 ` [PATCH v3 1/3] i2c/at91: add support for runtime PM Wenyou Yang
@ 2014-10-24 6:50 ` Wenyou Yang
[not found] ` <1414133417-11530-3-git-send-email-wenyou.yang-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
2014-11-08 18:03 ` Wolfram Sang
2014-10-24 6:50 ` [PATCH v3 3/3] i2c/at91: adopt pinctrl support Wenyou Yang
2014-10-29 8:24 ` [PATCH v3 0/3] i2c/at91: add support PM functions Ludovic Desroches
3 siblings, 2 replies; 12+ messages in thread
From: Wenyou Yang @ 2014-10-24 6:50 UTC (permalink / raw)
To: wsa-z923LK4zBo2bacvFa/9K2g,
ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w
Cc: linux-i2c-u79uwXL29TY76Z2rM5mHXA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA,
nicolas.ferre-AIFe0yeh4nAAvxtiuMwx3w,
khilman-DgEjT+Ai2ygdnm+yROfE0A,
linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r,
wenyou.yang-AIFe0yeh4nAAvxtiuMwx3w
Signed-off-by: Wenyou Yang <wenyou.yang-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
---
drivers/i2c/busses/i2c-at91.c | 26 ++++++++++++++++++++++++++
1 file changed, 26 insertions(+)
diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c
index a25fb5e..6a84a2a 100644
--- a/drivers/i2c/busses/i2c-at91.c
+++ b/drivers/i2c/busses/i2c-at91.c
@@ -861,7 +861,33 @@ static int at91_twi_runtime_resume(struct device *dev)
return clk_prepare_enable(twi_dev->clk);
}
+static int at91_twi_suspend_noirq(struct device *dev)
+{
+ if (!pm_runtime_status_suspended(dev))
+ at91_twi_runtime_suspend(dev);
+
+ return 0;
+}
+
+static int at91_twi_resume_noirq(struct device *dev)
+{
+ int ret;
+
+ if (!pm_runtime_status_suspended(dev)) {
+ ret = at91_twi_runtime_resume(dev);
+ if (ret)
+ return ret;
+ }
+
+ pm_runtime_mark_last_busy(dev);
+ pm_request_autosuspend(dev);
+
+ return 0;
+}
+
static const struct dev_pm_ops at91_twi_pm = {
+ .suspend_noirq = at91_twi_suspend_noirq,
+ .resume_noirq = at91_twi_resume_noirq,
.runtime_suspend = at91_twi_runtime_suspend,
.runtime_resume = at91_twi_runtime_resume,
};
--
1.7.9.5
^ permalink raw reply related [flat|nested] 12+ messages in thread[parent not found: <1414133417-11530-3-git-send-email-wenyou.yang-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>]
* Re: [PATCH v3 2/3] i2c/at91: add support for system PM
[not found] ` <1414133417-11530-3-git-send-email-wenyou.yang-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
@ 2014-10-24 13:02 ` Sergei Shtylyov
[not found] ` <544A4DED.6090009-M4DtvfQ/ZS1MRgGoP+s0PdBPR1lH4CV8@public.gmane.org>
0 siblings, 1 reply; 12+ messages in thread
From: Sergei Shtylyov @ 2014-10-24 13:02 UTC (permalink / raw)
To: Wenyou Yang, wsa-z923LK4zBo2bacvFa/9K2g,
ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w
Cc: khilman-DgEjT+Ai2ygdnm+yROfE0A,
nicolas.ferre-AIFe0yeh4nAAvxtiuMwx3w,
linux-kernel-u79uwXL29TY76Z2rM5mHXA,
linux-i2c-u79uwXL29TY76Z2rM5mHXA,
linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r
Hello.
On 10/24/2014 10:50 AM, Wenyou Yang wrote:
> Signed-off-by: Wenyou Yang <wenyou.yang-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
> ---
> drivers/i2c/busses/i2c-at91.c | 26 ++++++++++++++++++++++++++
> 1 file changed, 26 insertions(+)
> diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c
> index a25fb5e..6a84a2a 100644
> --- a/drivers/i2c/busses/i2c-at91.c
> +++ b/drivers/i2c/busses/i2c-at91.c
> @@ -861,7 +861,33 @@ static int at91_twi_runtime_resume(struct device *dev)
[...]
> +static int at91_twi_resume_noirq(struct device *dev)
> +{
> + int ret;
> +
> + if (!pm_runtime_status_suspended(dev)) {
> + ret = at91_twi_runtime_resume(dev);
Resume if *not* suspended?
> + if (ret)
> + return ret;
> + }
> +
> + pm_runtime_mark_last_busy(dev);
> + pm_request_autosuspend(dev);
> +
> + return 0;
> +}
> +
[...]
WBR, Sergei
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH v3 2/3] i2c/at91: add support for system PM
2014-10-24 6:50 ` [PATCH v3 2/3] i2c/at91: add support for system PM Wenyou Yang
[not found] ` <1414133417-11530-3-git-send-email-wenyou.yang-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
@ 2014-11-08 18:03 ` Wolfram Sang
1 sibling, 0 replies; 12+ messages in thread
From: Wolfram Sang @ 2014-11-08 18:03 UTC (permalink / raw)
To: Wenyou Yang
Cc: ludovic.desroches, linux-i2c, linux-kernel, nicolas.ferre,
khilman, linux-arm-kernel
[-- Attachment #1: Type: text/plain, Size: 145 bytes --]
On Fri, Oct 24, 2014 at 02:50:16PM +0800, Wenyou Yang wrote:
> Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Applied to for-next, thanks!
[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 819 bytes --]
^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH v3 3/3] i2c/at91: adopt pinctrl support
[not found] ` <1414133417-11530-1-git-send-email-wenyou.yang-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
2014-10-24 6:50 ` [PATCH v3 1/3] i2c/at91: add support for runtime PM Wenyou Yang
2014-10-24 6:50 ` [PATCH v3 2/3] i2c/at91: add support for system PM Wenyou Yang
@ 2014-10-24 6:50 ` Wenyou Yang
[not found] ` <1414133417-11530-4-git-send-email-wenyou.yang-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
2014-10-29 8:24 ` [PATCH v3 0/3] i2c/at91: add support PM functions Ludovic Desroches
3 siblings, 1 reply; 12+ messages in thread
From: Wenyou Yang @ 2014-10-24 6:50 UTC (permalink / raw)
To: wsa-z923LK4zBo2bacvFa/9K2g,
ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w
Cc: linux-i2c-u79uwXL29TY76Z2rM5mHXA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA,
nicolas.ferre-AIFe0yeh4nAAvxtiuMwx3w,
khilman-DgEjT+Ai2ygdnm+yROfE0A,
linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r,
wenyou.yang-AIFe0yeh4nAAvxtiuMwx3w
Amend the i2c at91 pin controller to optionally take a pin control
handle and set the state of the pins to:
- "default" on boot, resume and before performing an transfer
- "sleep" on suspend()
This should make it possible to optimize energy usage for the pins
both for the suspend/resume cycle
Signed-off-by: Wenyou Yang <wenyou.yang-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
---
drivers/i2c/busses/i2c-at91.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c
index 6a84a2a..290caf1 100644
--- a/drivers/i2c/busses/i2c-at91.c
+++ b/drivers/i2c/busses/i2c-at91.c
@@ -32,6 +32,7 @@
#include <linux/slab.h>
#include <linux/platform_data/dma-atmel.h>
#include <linux/pm_runtime.h>
+#include <linux/pinctrl/consumer.h>
#define DEFAULT_TWI_CLK_HZ 100000 /* max 400 Kbits/s */
#define AT91_I2C_TIMEOUT msecs_to_jiffies(100) /* transfer timeout */
@@ -747,6 +748,8 @@ static int at91_twi_probe(struct platform_device *pdev)
u32 phy_addr;
u32 bus_clk_rate;
+ pinctrl_pm_select_default_state(&pdev->dev);
+
dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
if (!dev)
return -ENOMEM;
@@ -851,6 +854,8 @@ static int at91_twi_runtime_suspend(struct device *dev)
clk_disable_unprepare(twi_dev->clk);
+ pinctrl_pm_select_sleep_state(dev);
+
return 0;
}
@@ -858,6 +863,8 @@ static int at91_twi_runtime_resume(struct device *dev)
{
struct at91_twi_dev *twi_dev = dev_get_drvdata(dev);
+ pinctrl_pm_select_default_state(dev);
+
return clk_prepare_enable(twi_dev->clk);
}
--
1.7.9.5
^ permalink raw reply related [flat|nested] 12+ messages in thread* Re: [PATCH v3 0/3] i2c/at91: add support PM functions
[not found] ` <1414133417-11530-1-git-send-email-wenyou.yang-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
` (2 preceding siblings ...)
2014-10-24 6:50 ` [PATCH v3 3/3] i2c/at91: adopt pinctrl support Wenyou Yang
@ 2014-10-29 8:24 ` Ludovic Desroches
2014-11-05 10:05 ` Yang, Wenyou
3 siblings, 1 reply; 12+ messages in thread
From: Ludovic Desroches @ 2014-10-29 8:24 UTC (permalink / raw)
To: Wenyou Yang
Cc: wsa-z923LK4zBo2bacvFa/9K2g,
ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w,
linux-i2c-u79uwXL29TY76Z2rM5mHXA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA,
nicolas.ferre-AIFe0yeh4nAAvxtiuMwx3w,
khilman-DgEjT+Ai2ygdnm+yROfE0A,
linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r
For the whole serie
Acked-by: Ludovic Desroches <ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
On Fri, Oct 24, 2014 at 02:50:14PM +0800, Wenyou Yang wrote:
> Hi Wolfram,
>
> The patches is to add the PM functions support for the at91 i2c controller.
>
> It is based on the i2c/for-next branch of
> git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux.git.
>
> Best Regards,
> Wenyou Yang
>
> ------
> Change log:
> v2.0
>
> According to the advice from Kevin Hilman,
> 1./ Wrap the runtime suspend/resume functions in CONFIG_PM instead of CONFIG_PM_RUNTIME.
> 2./ Call the runtime suspend/resume functions directly in the system suspend/resume.
>
> v3.0
> Covert the system suspend/resume to suspend_noirq/resume_noirq.
>
> Wenyou Yang (3):
> i2c/at91: add support for runtime PM
> i2c/at91: add support for system PM
> i2c/at91: adopt pinctrl support
>
> drivers/i2c/busses/i2c-at91.c | 71 +++++++++++++++++++++++++++++++++++++----
> 1 file changed, 65 insertions(+), 6 deletions(-)
>
> --
> 1.7.9.5
>
^ permalink raw reply [flat|nested] 12+ messages in thread* RE: [PATCH v3 0/3] i2c/at91: add support PM functions
2014-10-29 8:24 ` [PATCH v3 0/3] i2c/at91: add support PM functions Ludovic Desroches
@ 2014-11-05 10:05 ` Yang, Wenyou
0 siblings, 0 replies; 12+ messages in thread
From: Yang, Wenyou @ 2014-11-05 10:05 UTC (permalink / raw)
To: Desroches, Ludovic, wsa-z923LK4zBo2bacvFa/9K2g@public.gmane.org
Cc: linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
Ferre, Nicolas, khilman-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org,
linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org
Hi Wolfram,
Could you give me some advice? Thank you in advance.
> -----Original Message-----
> From: Ludovic Desroches [mailto:ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org]
> Sent: Wednesday, October 29, 2014 4:24 PM
> To: Yang, Wenyou
> Cc: wsa-z923LK4zBo2bacvFa/9K2g@public.gmane.org; Desroches, Ludovic; linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org; linux-
> kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org; Ferre, Nicolas; khilman-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org; linux-arm-
> kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org
> Subject: Re: [PATCH v3 0/3] i2c/at91: add support PM functions
>
> For the whole serie
>
> Acked-by: Ludovic Desroches <ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
>
> On Fri, Oct 24, 2014 at 02:50:14PM +0800, Wenyou Yang wrote:
> > Hi Wolfram,
> >
> > The patches is to add the PM functions support for the at91 i2c controller.
> >
> > It is based on the i2c/for-next branch of
> > git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux.git.
> >
> > Best Regards,
> > Wenyou Yang
> >
> > ------
> > Change log:
> > v2.0
> >
> > According to the advice from Kevin Hilman, 1./ Wrap the runtime
> > suspend/resume functions in CONFIG_PM instead of CONFIG_PM_RUNTIME.
> > 2./ Call the runtime suspend/resume functions directly in the system
> suspend/resume.
> >
> > v3.0
> > Covert the system suspend/resume to suspend_noirq/resume_noirq.
> >
> > Wenyou Yang (3):
> > i2c/at91: add support for runtime PM
> > i2c/at91: add support for system PM
> > i2c/at91: adopt pinctrl support
> >
> > drivers/i2c/busses/i2c-at91.c | 71
> +++++++++++++++++++++++++++++++++++++----
> > 1 file changed, 65 insertions(+), 6 deletions(-)
> >
> > --
> > 1.7.9.5
> >
Best Regards,
Wenyou Yang
^ permalink raw reply [flat|nested] 12+ messages in thread