Subject: [PATCH 1/9] Staging/iio/adc/touchscreen/MXS: add proper clock handling

From: [email-masked] (Jonathan Cameron)
Date: Tue, 01 Oct 2013 11:57:40 +0100

On 09/24/13 08:50, J?rgen Beisert wrote:
> Hi Fabio,
> 
> On Monday 23 September 2013 17:13:03 Fabio Estevam wrote:
>> On 09/23/2013 11:36 AM, Juergen Beisert wrote:
>>> +	lradc->clk = devm_clk_get(&pdev->dev, NULL);
>>> +	clk_prepare_enable(lradc->clk);
>>
>> clk_prepare_enable() may fail, so better check its return value.
> 
> Thanks for the comment. Better this way?
> 
> commit 825c5bb787a0dc9d25d480178e117be08810639c
> Author: Juergen Beisert <[email-masked]>
> Date:   Mon Sep 23 16:10:56 2013 +0200
Applied.  If you are going to have a new patch version in the middle of the thread
please generate it with git format-patch and then send it as a reply to the email
you are responding to.  Applying a patch like this is no where near as easy.

Applied to the togreg branch of iio.git

Thanks
> 
>     Staging/iio/adc/touchscreen/MXS: add proper clock handling
>     
>     The delay units inside the LRADC depend on the presence of a 2 kHz clock.
>     This change enables the clock to be able to use the delay unit for the
>     touchscreen part of the driver.
>     
>     Signed-off-by: Juergen Beisert <[email-masked]>
> 
> diff --git a/arch/arm/boot/dts/imx23.dtsi b/arch/arm/boot/dts/imx23.dtsi
> index 28b5ce2..07caf76 100644
> --- a/arch/arm/boot/dts/imx23.dtsi
> +++ b/arch/arm/boot/dts/imx23.dtsi
> @@ -430,6 +430,7 @@
>  				reg = <0x80050000 0x2000>;
>  				interrupts = <36 37 38 39 40 41 42 43 44>;
>  				status = "disabled";
> +				clocks = <&clks 26>;
>  			};
>  
>  			spdif at 80054000 {
> diff --git a/arch/arm/boot/dts/imx28.dtsi b/arch/arm/boot/dts/imx28.dtsi
> index 7363fde..175deef 100644
> --- a/arch/arm/boot/dts/imx28.dtsi
> +++ b/arch/arm/boot/dts/imx28.dtsi
> @@ -902,6 +902,7 @@
>  				interrupts = <10 14 15 16 17 18 19
>  						20 21 22 23 24 25>;
>  				status = "disabled";
> +				clocks = <&clks 41>;
>  			};
>  
>  			spdif: spdif at 80054000 {
> diff --git a/drivers/staging/iio/adc/mxs-lradc.c b/drivers/staging/iio/adc/mxs-lradc.c
> index a08c173..eaca1ae 100644
> --- a/drivers/staging/iio/adc/mxs-lradc.c
> +++ b/drivers/staging/iio/adc/mxs-lradc.c
> @@ -35,6 +35,7 @@
>  #include <linux/completion.h>
>  #include <linux/delay.h>
>  #include <linux/input.h>
> +#include <linux/clk.h>
>  
>  #include <linux/iio/iio.h>
>  #include <linux/iio/buffer.h>
> @@ -134,6 +135,8 @@ struct mxs_lradc {
>  	void __iomem		*base;
>  	int			irq[13];
>  
> +	struct clk		*clk;
> +
>  	uint32_t		*buffer;
>  	struct iio_trigger	*trig;
>  
> @@ -928,6 +931,17 @@ static int mxs_lradc_probe(struct platform_device *pdev)
>  	if (IS_ERR(lradc->base))
>  		return PTR_ERR(lradc->base);
>  
> +	lradc->clk = devm_clk_get(&pdev->dev, NULL);
> +	if (IS_ERR(lradc->clk)) {
> +		dev_err(dev, "Failed to get the delay unit clock\n");
> +		return PTR_ERR(lradc->clk);
> +	}
> +	ret = clk_prepare_enable(lradc->clk);
> +	if (ret != 0) {
> +		dev_err(dev, "Failed to enable the delay unit clock\n");
> +		return ret;
> +	}
> +
>  	INIT_WORK(&lradc->ts_work, mxs_lradc_ts_work);
>  
>  	/* Check if touchscreen is enabled in DT. */
> @@ -1020,6 +1034,7 @@ static int mxs_lradc_remove(struct platform_device *pdev)
>  	iio_triggered_buffer_cleanup(iio);
>  	mxs_lradc_trigger_remove(iio);
>  
> +	clk_disable_unprepare(lradc->clk);
>  	return 0;
>  }
>  
> Juergen
>