On Tue, 26 Jan 2016, Andy Shevchenko wrote:
> From: Heikki Krogerus <heikki.kroge...@linux.intel.com>
>
> All configurations are lost and the registers will have
> default values when the hardware is suspended and resumed,
> so saving the private register space context on suspend, and
> restoring it on resume.
>
> Fixes: 4b45efe85263 (mfd: Add support for Intel Sunrisepoint LPSS devices)
I'd say this sumbission is more of a functional extention than a
bug-fix. No real need for this statement.
> Signed-off-by: Heikki Krogerus <heikki.kroge...@linux.intel.com>
> Signed-off-by: Mika Westerberg <mika.westerb...@linux.intel.com>
Did it really take 2 of you to write this patch?
> Signed-off-by: Andy Shevchenko <andriy.shevche...@linux.intel.com>
> ---
> drivers/mfd/intel-lpss.c | 19 ++++++++++++++++++-
> 1 file changed, 18 insertions(+), 1 deletion(-)
Code looks okay though:
Acked-by: Lee Jones <lee.jo...@linaro.org>
> diff --git a/drivers/mfd/intel-lpss.c b/drivers/mfd/intel-lpss.c
> index 1743788..2a7c6a7 100644
> --- a/drivers/mfd/intel-lpss.c
> +++ b/drivers/mfd/intel-lpss.c
> @@ -34,6 +34,7 @@
> #define LPSS_DEV_SIZE 0x200
> #define LPSS_PRIV_OFFSET 0x200
> #define LPSS_PRIV_SIZE 0x100
> +#define LPSS_PRIV_REG_COUNT (LPSS_PRIV_SIZE / 4)
> #define LPSS_IDMA64_OFFSET 0x800
> #define LPSS_IDMA64_SIZE 0x800
>
> @@ -76,6 +77,7 @@ struct intel_lpss {
> struct mfd_cell *cell;
> struct device *dev;
> void __iomem *priv;
> + u32 priv_ctx[LPSS_PRIV_REG_COUNT];
> int devid;
> u32 caps;
> u32 active_ltr;
> @@ -492,6 +494,16 @@ EXPORT_SYMBOL_GPL(intel_lpss_prepare);
>
> int intel_lpss_suspend(struct device *dev)
> {
> + struct intel_lpss *lpss = dev_get_drvdata(dev);
> + unsigned int i;
> +
> + /* Save device context */
> + for (i = 0; i < LPSS_PRIV_REG_COUNT; i++)
> + lpss->priv_ctx[i] = readl(lpss->priv + i * 4);
> +
> + /* Put the device into reset state */
> + writel(0, lpss->priv + LPSS_PRIV_RESETS);
> +
> return 0;
> }
> EXPORT_SYMBOL_GPL(intel_lpss_suspend);
> @@ -499,8 +511,13 @@ EXPORT_SYMBOL_GPL(intel_lpss_suspend);
> int intel_lpss_resume(struct device *dev)
> {
> struct intel_lpss *lpss = dev_get_drvdata(dev);
> + unsigned int i;
>
> - intel_lpss_init_dev(lpss);
> + intel_lpss_deassert_reset(lpss);
> +
> + /* Restore device context */
> + for (i = 0; i < LPSS_PRIV_REG_COUNT; i++)
> + writel(lpss->priv_ctx[i], lpss->priv + i * 4);
>
> return 0;
> }
--
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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