* [PATCH v2] i2c-mpc: avoid I2C abnormal after resuming from deep sleep
@ 2012-04-19 9:51 ` Zhao Chenhui
0 siblings, 0 replies; 4+ messages in thread
From: Zhao Chenhui @ 2012-04-19 9:51 UTC (permalink / raw)
To: linux-i2c; +Cc: w.sang, leoli, linux-kernel
When entering deep sleep, the value in the registers I2CFDR and
I2CDFSRR are lost. This causes I2C access to fail after resuming.
Add suspend/resume routines to save/restore the registers
I2CFDR and I2CDFSRR.
Signed-off-by: Zhao Chenhui <chenhui.zhao@freescale.com>
Signed-off-by: Li Yang <leoli@freescale.com>
---
drivers/i2c/busses/i2c-mpc.c | 30 ++++++++++++++++++++++++++++++
1 files changed, 30 insertions(+), 0 deletions(-)
diff --git a/drivers/i2c/busses/i2c-mpc.c b/drivers/i2c/busses/i2c-mpc.c
index a8ebb84..fb2627b 100644
--- a/drivers/i2c/busses/i2c-mpc.c
+++ b/drivers/i2c/busses/i2c-mpc.c
@@ -64,6 +64,9 @@ struct mpc_i2c {
struct i2c_adapter adap;
int irq;
u32 real_clk;
+#ifdef CONFIG_PM
+ u8 fdr, dfsrr;
+#endif
};
struct mpc_i2c_divider {
@@ -668,6 +671,30 @@ static int __devexit fsl_i2c_remove(struct platform_device *op)
return 0;
};
+#ifdef CONFIG_PM
+static int mpc_i2c_suspend(struct device *dev)
+{
+ struct mpc_i2c *i2c = dev_get_drvdata(dev);
+
+ i2c->fdr = readb(i2c->base + MPC_I2C_FDR);
+ i2c->dfsrr = readb(i2c->base + MPC_I2C_DFSRR);
+
+ return 0;
+}
+
+static int mpc_i2c_resume(struct device *dev)
+{
+ struct mpc_i2c *i2c = dev_get_drvdata(dev);
+
+ writeb(i2c->fdr, i2c->base + MPC_I2C_FDR);
+ writeb(i2c->dfsrr, i2c->base + MPC_I2C_DFSRR);
+
+ return 0;
+}
+
+SIMPLE_DEV_PM_OPS(mpc_i2c_pm_ops, mpc_i2c_suspend, mpc_i2c_resume);
+#endif
+
static struct mpc_i2c_data mpc_i2c_data_512x __devinitdata = {
.setup = mpc_i2c_setup_512x,
};
@@ -712,6 +739,9 @@ static struct platform_driver mpc_i2c_driver = {
.owner = THIS_MODULE,
.name = DRV_NAME,
.of_match_table = mpc_i2c_of_match,
+#ifdef CONFIG_PM
+ .pm = &mpc_i2c_pm_ops,
+#endif
},
};
--
1.6.4.1
^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH v2] i2c-mpc: avoid I2C abnormal after resuming from deep sleep
@ 2012-04-19 9:51 ` Zhao Chenhui
0 siblings, 0 replies; 4+ messages in thread
From: Zhao Chenhui @ 2012-04-19 9:51 UTC (permalink / raw)
To: linux-i2c-u79uwXL29TY76Z2rM5mHXA
Cc: w.sang-bIcnvbaLZ9MEGnE8C9+IrQ, leoli-KZfg59tc24xl57MIdRCFDg,
linux-kernel-u79uwXL29TY76Z2rM5mHXA
When entering deep sleep, the value in the registers I2CFDR and
I2CDFSRR are lost. This causes I2C access to fail after resuming.
Add suspend/resume routines to save/restore the registers
I2CFDR and I2CDFSRR.
Signed-off-by: Zhao Chenhui <chenhui.zhao-KZfg59tc24xl57MIdRCFDg@public.gmane.org>
Signed-off-by: Li Yang <leoli-KZfg59tc24xl57MIdRCFDg@public.gmane.org>
---
drivers/i2c/busses/i2c-mpc.c | 30 ++++++++++++++++++++++++++++++
1 files changed, 30 insertions(+), 0 deletions(-)
diff --git a/drivers/i2c/busses/i2c-mpc.c b/drivers/i2c/busses/i2c-mpc.c
index a8ebb84..fb2627b 100644
--- a/drivers/i2c/busses/i2c-mpc.c
+++ b/drivers/i2c/busses/i2c-mpc.c
@@ -64,6 +64,9 @@ struct mpc_i2c {
struct i2c_adapter adap;
int irq;
u32 real_clk;
+#ifdef CONFIG_PM
+ u8 fdr, dfsrr;
+#endif
};
struct mpc_i2c_divider {
@@ -668,6 +671,30 @@ static int __devexit fsl_i2c_remove(struct platform_device *op)
return 0;
};
+#ifdef CONFIG_PM
+static int mpc_i2c_suspend(struct device *dev)
+{
+ struct mpc_i2c *i2c = dev_get_drvdata(dev);
+
+ i2c->fdr = readb(i2c->base + MPC_I2C_FDR);
+ i2c->dfsrr = readb(i2c->base + MPC_I2C_DFSRR);
+
+ return 0;
+}
+
+static int mpc_i2c_resume(struct device *dev)
+{
+ struct mpc_i2c *i2c = dev_get_drvdata(dev);
+
+ writeb(i2c->fdr, i2c->base + MPC_I2C_FDR);
+ writeb(i2c->dfsrr, i2c->base + MPC_I2C_DFSRR);
+
+ return 0;
+}
+
+SIMPLE_DEV_PM_OPS(mpc_i2c_pm_ops, mpc_i2c_suspend, mpc_i2c_resume);
+#endif
+
static struct mpc_i2c_data mpc_i2c_data_512x __devinitdata = {
.setup = mpc_i2c_setup_512x,
};
@@ -712,6 +739,9 @@ static struct platform_driver mpc_i2c_driver = {
.owner = THIS_MODULE,
.name = DRV_NAME,
.of_match_table = mpc_i2c_of_match,
+#ifdef CONFIG_PM
+ .pm = &mpc_i2c_pm_ops,
+#endif
},
};
--
1.6.4.1
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH v2] i2c-mpc: avoid I2C abnormal after resuming from deep sleep
@ 2012-04-19 11:07 ` Wolfram Sang
0 siblings, 0 replies; 4+ messages in thread
From: Wolfram Sang @ 2012-04-19 11:07 UTC (permalink / raw)
To: Zhao Chenhui; +Cc: linux-i2c, leoli, linux-kernel
[-- Attachment #1: Type: text/plain, Size: 589 bytes --]
On Thu, Apr 19, 2012 at 05:51:34PM +0800, Zhao Chenhui wrote:
> When entering deep sleep, the value in the registers I2CFDR and
> I2CDFSRR are lost. This causes I2C access to fail after resuming.
>
> Add suspend/resume routines to save/restore the registers
> I2CFDR and I2CDFSRR.
>
> Signed-off-by: Zhao Chenhui <chenhui.zhao@freescale.com>
> Signed-off-by: Li Yang <leoli@freescale.com>
Applied to next. Thanks!
--
Pengutronix e.K. | Wolfram Sang |
Industrial Linux Solutions | http://www.pengutronix.de/ |
[-- Attachment #2: Digital signature --]
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^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH v2] i2c-mpc: avoid I2C abnormal after resuming from deep sleep
@ 2012-04-19 11:07 ` Wolfram Sang
0 siblings, 0 replies; 4+ messages in thread
From: Wolfram Sang @ 2012-04-19 11:07 UTC (permalink / raw)
To: Zhao Chenhui
Cc: linux-i2c-u79uwXL29TY76Z2rM5mHXA, leoli-KZfg59tc24xl57MIdRCFDg,
linux-kernel-u79uwXL29TY76Z2rM5mHXA
[-- Attachment #1: Type: text/plain, Size: 641 bytes --]
On Thu, Apr 19, 2012 at 05:51:34PM +0800, Zhao Chenhui wrote:
> When entering deep sleep, the value in the registers I2CFDR and
> I2CDFSRR are lost. This causes I2C access to fail after resuming.
>
> Add suspend/resume routines to save/restore the registers
> I2CFDR and I2CDFSRR.
>
> Signed-off-by: Zhao Chenhui <chenhui.zhao-KZfg59tc24xl57MIdRCFDg@public.gmane.org>
> Signed-off-by: Li Yang <leoli-KZfg59tc24xl57MIdRCFDg@public.gmane.org>
Applied to next. Thanks!
--
Pengutronix e.K. | Wolfram Sang |
Industrial Linux Solutions | http://www.pengutronix.de/ |
[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 198 bytes --]
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2012-04-19 11:07 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
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2012-04-19 9:51 [PATCH v2] i2c-mpc: avoid I2C abnormal after resuming from deep sleep Zhao Chenhui
2012-04-19 9:51 ` Zhao Chenhui
2012-04-19 11:07 ` Wolfram Sang
2012-04-19 11:07 ` Wolfram Sang
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