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 <[email protected]>
Signed-off-by: Li Yang <[email protected]>
---
drivers/i2c/busses/i2c-mpc.c | 34 +++++++++++++++++++++++++++++++++-
1 files changed, 33 insertions(+), 1 deletions(-)
diff --git a/drivers/i2c/busses/i2c-mpc.c b/drivers/i2c/busses/i2c-mpc.c
index a8ebb84..f95a647 100644
--- a/drivers/i2c/busses/i2c-mpc.c
+++ b/drivers/i2c/busses/i2c-mpc.c
@@ -1,7 +1,9 @@
/*
* (C) Copyright 2003-2004
* Humboldt Solutions Ltd, [email protected].
-
+ *
+ * Copyright 2012 Freescale Semiconductor, Inc.
+ *
* This is a combined i2c adapter and algorithm driver for the
* MPC107/Tsi107 PowerPC northbridge and processors that include
* the same I2C unit (8240, 8245, 85xx).
@@ -64,6 +66,9 @@ 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 +673,30 @@ 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 +741,9 @@ 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
Hi Zhao,
On Wed, Feb 29, 2012 at 4:09 PM, Zhao Chenhui
<[email protected]> 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 <[email protected]>
> Signed-off-by: Li Yang <[email protected]>
> ---
> ?drivers/i2c/busses/i2c-mpc.c | ? 34 +++++++++++++++++++++++++++++++++-
> ?1 files changed, 33 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/i2c/busses/i2c-mpc.c b/drivers/i2c/busses/i2c-mpc.c
> index a8ebb84..f95a647 100644
> --- a/drivers/i2c/busses/i2c-mpc.c
> +++ b/drivers/i2c/busses/i2c-mpc.c
> @@ -1,7 +1,9 @@
> ?/*
> ?* (C) Copyright 2003-2004
> ?* Humboldt Solutions Ltd, [email protected].
> -
> + *
> + * Copyright 2012 Freescale Semiconductor, Inc.
> + *
> ?* This is a combined i2c adapter and algorithm driver for the
> ?* MPC107/Tsi107 PowerPC northbridge and processors that include
> ?* the same I2C unit (8240, 8245, 85xx).
> @@ -64,6 +66,9 @@ struct mpc_i2c {
> ? ? ? ?struct i2c_adapter adap;
> ? ? ? ?int irq;
> ? ? ? ?u32 real_clk;
> +#ifdef CONFIG_PM
> + ? ? ? u8 fdr, dfsrr;
How about having a structure here ?
> +#endif
> ?};
>
> ?struct mpc_i2c_divider {
> @@ -668,6 +673,30 @@ 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 +741,9 @@ 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
>
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-i2c" in
> the body of a message to [email protected]
> More majordomo info at ?http://vger.kernel.org/majordomo-info.html
On Wed, Feb 29, 2012 at 7:02 AM, Shubhrajyoti Datta
<[email protected]> wrote:
>
>> +#ifdef CONFIG_PM
>> + ? ? ? u8 fdr, dfsrr;
> How about having ?a structure here ?
Why? He's just adding two variables in an existing structure. Adding
a nested structure would unnecessarily complicate things.
--
Timur Tabi
Linux kernel developer at Freescale
Hi,
On Wed, Feb 29, 2012 at 06:39:21PM +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 <[email protected]>
> Signed-off-by: Li Yang <[email protected]>
> ---
> drivers/i2c/busses/i2c-mpc.c | 34 +++++++++++++++++++++++++++++++++-
> 1 files changed, 33 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/i2c/busses/i2c-mpc.c b/drivers/i2c/busses/i2c-mpc.c
> index a8ebb84..f95a647 100644
> --- a/drivers/i2c/busses/i2c-mpc.c
> +++ b/drivers/i2c/busses/i2c-mpc.c
> @@ -1,7 +1,9 @@
> /*
> * (C) Copyright 2003-2004
> * Humboldt Solutions Ltd, [email protected].
> -
> + *
> + * Copyright 2012 Freescale Semiconductor, Inc.
> + *
I'd think the change is too trivial to claim copyright on the file.
Thanks for the contribution,
Wolfram
--
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