Re: [PATCH 8/9] arm: twr-k70f120m: extend Freescale eDMA driver with ability to support Kinetis SoC

[Paul Osmialowski <pawelo@king.net.pl>]

Hi Vinod,

Tanks for your comments. Actually, fsl-lpuart driver is done the way you 
propose to rework this one. I'll consider this during my work on the 
second iteration.

On Wed, 24 Jun 2015, Vinod Koul wrote:

> On Tue, Jun 23, 2015 at 11:19:46PM +0200, Paul Osmialowski wrote:
>> Surprisingly small amount of work was required in order to extend already
>> existing eDMA driver with the support for Kinetis SoC architecture.
>>
>> Note that <mach/memory.h> is needed (which is denoted by
>> CONFIG_NEED_MACH_MEMORY_H) as it provides macros required for proper
>> operation of DMA allocation functions.
>>
>> Signed-off-by: Paul Osmialowski <pawelo@king.net.pl>
>> ---
>>  Documentation/devicetree/bindings/dma/fsl-edma.txt | 38 +++++++++-
>>  arch/arm/Kconfig                                   |  4 ++
>>  arch/arm/boot/dts/kinetis.dtsi                     | 34 +++++++++
>>  arch/arm/mach-kinetis/include/mach/memory.h        | 61 ++++++++++++++++
>>  drivers/clk/clk-kinetis.c                          | 15 ++++
>>  drivers/dma/fsl-edma.c                             | 81 +++++++++++++++++++++-
>>  include/dt-bindings/clock/kinetis-mcg.h            |  5 +-
> having so many change into one patch is not a great idea, please breka them
> up. I am looking for single/multiple patches which only touch dmaengine
> files
>
>
>> +#ifdef CONFIG_ARCH_KINETIS
>> +static const char * const txirq_names[] = {
>> +	"edma-tx-0,16",
>> +	"edma-tx-1,17",
>> +	"edma-tx-2,18",
>> +	"edma-tx-3,19",
>> +	"edma-tx-4,20",
>> +	"edma-tx-5,21",
>> +	"edma-tx-6,22",
>> +	"edma-tx-7,23",
>> +	"edma-tx-8,24",
>> +	"edma-tx-9,25",
>> +	"edma-tx-10,26",
>> +	"edma-tx-11,27",
>> +	"edma-tx-12,28",
>> +	"edma-tx-13,29",
>> +	"edma-tx-14,30",
>> +	"edma-tx-15,31",
>> +};
> why do we need this array, these seem to come from DT, right?
>> +#endif
>> +
>>  struct fsl_edma_engine {
>>  	struct dma_device	dma_dev;
>>  	void __iomem		*membase;
>> +#ifdef CONFIG_ARCH_KINETIS
>> +	struct clk		*clk;
>> +#endif
>>  	void __iomem		*muxbase[DMAMUX_NR];
>>  	struct clk		*muxclk[DMAMUX_NR];
>>  	struct mutex		fsl_edma_mutex;
>>  	u32			n_chans;
>> +#ifdef CONFIG_ARCH_KINETIS
>> +	int			txirq[ARRAY_SIZE(txirq_names)];
>> +#else
>>  	int			txirq;
>> +#endif
>>  	int			errirq;
>>  	bool			big_endian;
>>  	struct fsl_edma_chan	chans[];
> we can define these bits and only be used on kinetis machines?
>
>> @@ -709,6 +737,7 @@ static irqreturn_t fsl_edma_err_handler(int irq, void *dev_id)
>>  	return IRQ_HANDLED;
>>  }
>>
>> +#ifndef CONFIG_ARCH_KINETIS
>>  static irqreturn_t fsl_edma_irq_handler(int irq, void *dev_id)
>>  {
>>  	if (fsl_edma_tx_handler(irq, dev_id) == IRQ_HANDLED)
>> @@ -716,6 +745,7 @@ static irqreturn_t fsl_edma_irq_handler(int irq, void *dev_id)
>>
>>  	return fsl_edma_err_handler(irq, dev_id);
>>  }
>> +#endif
>>
>>  static void fsl_edma_issue_pending(struct dma_chan *chan)
>>  {
>> @@ -788,15 +818,29 @@ static void fsl_edma_free_chan_resources(struct dma_chan *chan)
>>  }
>>
>>  static int
>> -fsl_edma_irq_init(struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
>> +fsl_edma_irq_init(struct platform_device *pdev,
>> +		  struct fsl_edma_engine *fsl_edma)
>>  {
>>  	int ret;
>> +#ifdef CONFIG_ARCH_KINETIS
>> +	int i;
>>
>> +	for (i = 0; i < ARRAY_SIZE(txirq_names); i++) {
>> +		fsl_edma->txirq[i] = platform_get_irq_byname(pdev,
>> +					txirq_names[i]);
>> +		if (fsl_edma->txirq[i] < 0) {
>> +			dev_err(&pdev->dev, "Can't get %s irq.\n",
>> +						txirq_names[i]);
>> +			return fsl_edma->txirq[i];
>> +		}
>> +	}
>> +#else
>>  	fsl_edma->txirq = platform_get_irq_byname(pdev, "edma-tx");
>>  	if (fsl_edma->txirq < 0) {
>>  		dev_err(&pdev->dev, "Can't get edma-tx irq.\n");
>>  		return fsl_edma->txirq;
>>  	}
>> +#endif
> can you have two routines and with one of them onvoked based on machine type
> which should be configured based on DT data rather
>
>>
>>  	fsl_edma->errirq = platform_get_irq_byname(pdev, "edma-err");
>>  	if (fsl_edma->errirq < 0) {
>> @@ -804,6 +848,16 @@ fsl_edma_irq_init(struct platform_device *pdev, struct fsl_edma_engine *fsl_edma
>>  		return fsl_edma->errirq;
>>  	}
>>
>> +#ifdef CONFIG_ARCH_KINETIS
>> +	for (i = 0; i < ARRAY_SIZE(txirq_names); i++) {
>> +		ret = devm_request_irq(&pdev->dev, fsl_edma->txirq[i],
>> +			fsl_edma_tx_handler, 0, txirq_names[i], fsl_edma);
>> +		if (ret) {
>> +			dev_err(&pdev->dev, "Can't register eDMA tx IRQ.\n");
>> +			return  ret;
>> +		}
>> +	}
>> +#else
>>  	if (fsl_edma->txirq == fsl_edma->errirq) {
>>  		ret = devm_request_irq(&pdev->dev, fsl_edma->txirq,
>>  				fsl_edma_irq_handler, 0, "eDMA", fsl_edma);
>> @@ -818,6 +872,7 @@ fsl_edma_irq_init(struct platform_device *pdev, struct fsl_edma_engine *fsl_edma
>>  			dev_err(&pdev->dev, "Can't register eDMA tx IRQ.\n");
>>  			return  ret;
>>  		}
>> +#endif
> only one of them will be populated so if-else should work too
>
> please get rid of these ifdef stuff and make it based on DT data based flags
>
> -- 
> ~Vinod
>