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Commit 26aafa77 authored by Shawn Guo's avatar Shawn Guo
Browse files

spi: mxs-spi: move to use generic DMA helper 



With the generic DMA device tree helper supported by mxs-dma driver,
client devices only need to call dma_request_slave_channel() for
requesting a DMA channel from dmaengine.

Since mxs is a DT only platform now, along with the changes, the non-DT
case handling in probe function also gets removed.

Signed-off-by: default avatarShawn Guo <shawn.guo@linaro.org>
Acked-by: default avatarGrant Likely <grant.likely@secretlab.ca>
Reviewed-by: default avatarArnd Bergmann <arnd@arndb.de>
parent 0e91e434

Documentation/devicetree/bindings/spi/mxs-spi.txt

+8 −4
Original line number Original line Diff line number Diff line
@@ -3,8 +3,11 @@ 
Required properties:

Required properties:

- compatible: Should be "fsl,<soc>-spi", where soc is "imx23" or "imx28"

- compatible: Should be "fsl,<soc>-spi", where soc is "imx23" or "imx28"

- reg: Offset and length of the register set for the device

- reg: Offset and length of the register set for the device

- interrupts: Should contain SSP interrupts (error irq first, dma irq second)

- interrupts: Should contain SSP ERROR interrupt

- fsl,ssp-dma-channel: APBX DMA channel for the SSP

- dmas: DMA specifier, consisting of a phandle to DMA controller node

  and SSP DMA channel ID.

  Refer to dma.txt and fsl-mxs-dma.txt for details.

- dma-names: Must be "rx-tx".





Optional properties:

Optional properties:

- clock-frequency : Input clock frequency to the SPI block in Hz.

- clock-frequency : Input clock frequency to the SPI block in Hz.
@@ -17,6 +20,7 @@ ssp0: ssp@80010000 { 
	#size-cells = <0>;

	#size-cells = <0>;

	compatible = "fsl,imx28-spi";

	compatible = "fsl,imx28-spi";

	reg = <0x80010000 0x2000>;

	reg = <0x80010000 0x2000>;

	interrupts = <96 82>;

	interrupts = <96>;

	fsl,ssp-dma-channel = <0>;

	dmas = <&dma_apbh 0>;

	dma-names = "rx-tx";

};
 
};

drivers/spi/spi-mxs.c

+9 −51
Original line number Original line Diff line number Diff line
@@ -490,21 +490,6 @@ static int mxs_spi_transfer_one(struct spi_master *master, 
	return status;

	return status;

}

}





static bool mxs_ssp_dma_filter(struct dma_chan *chan, void *param)

{

	struct mxs_ssp *ssp = param;



	if (!mxs_dma_is_apbh(chan))

		return false;



	if (chan->chan_id != ssp->dma_channel)

		return false;



	chan->private = &ssp->dma_data;



	return true;

}



static const struct of_device_id mxs_spi_dt_ids[] = {

static const struct of_device_id mxs_spi_dt_ids[] = {

	{ .compatible = "fsl,imx23-spi", .data = (void *) IMX23_SSP, },

	{ .compatible = "fsl,imx23-spi", .data = (void *) IMX23_SSP, },

	{ .compatible = "fsl,imx28-spi", .data = (void *) IMX28_SSP, },

	{ .compatible = "fsl,imx28-spi", .data = (void *) IMX28_SSP, },
@@ -520,13 +505,12 @@ static int mxs_spi_probe(struct platform_device *pdev) 
	struct spi_master *master;

	struct spi_master *master;

	struct mxs_spi *spi;

	struct mxs_spi *spi;

	struct mxs_ssp *ssp;

	struct mxs_ssp *ssp;

	struct resource *iores, *dmares;

	struct resource *iores;

	struct pinctrl *pinctrl;

	struct pinctrl *pinctrl;

	struct clk *clk;

	struct clk *clk;

	void __iomem *base;

	void __iomem *base;

	int devid, dma_channel, clk_freq;

	int devid, clk_freq;

	int ret = 0, irq_err, irq_dma;

	int ret = 0, irq_err;

	dma_cap_mask_t mask;





	/*

	/*

	 * Default clock speed for the SPI core. 160MHz seems to

	 * Default clock speed for the SPI core. 160MHz seems to
@@ -537,8 +521,7 @@ static int mxs_spi_probe(struct platform_device *pdev) 




	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);

	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);

	irq_err = platform_get_irq(pdev, 0);

	irq_err = platform_get_irq(pdev, 0);

	irq_dma = platform_get_irq(pdev, 1);

	if (!iores || irq_err < 0)

	if (!iores || irq_err < 0 || irq_dma < 0)

		return -EINVAL;

		return -EINVAL;





	base = devm_ioremap_resource(&pdev->dev, iores);

	base = devm_ioremap_resource(&pdev->dev, iores);
@@ -553,32 +536,11 @@ static int mxs_spi_probe(struct platform_device *pdev) 
	if (IS_ERR(clk))

	if (IS_ERR(clk))

		return PTR_ERR(clk);

		return PTR_ERR(clk);





	if (np) {

	devid = (enum mxs_ssp_id) of_id->data;

	devid = (enum mxs_ssp_id) of_id->data;

		/*

		 * TODO: This is a temporary solution and should be changed

		 * to use generic DMA binding later when the helpers get in.

		 */

		ret = of_property_read_u32(np, "fsl,ssp-dma-channel",

					   &dma_channel);

		if (ret) {

			dev_err(&pdev->dev,

				"Failed to get DMA channel\n");

			return -EINVAL;

		}



	ret = of_property_read_u32(np, "clock-frequency",

	ret = of_property_read_u32(np, "clock-frequency",

				   &clk_freq);

				   &clk_freq);

	if (ret)

	if (ret)

		clk_freq = clk_freq_default;

		clk_freq = clk_freq_default;

	} else {

		dmares = platform_get_resource(pdev, IORESOURCE_DMA, 0);

		if (!dmares)

			return -EINVAL;

		devid = pdev->id_entry->driver_data;

		dma_channel = dmares->start;

		clk_freq = clk_freq_default;

	}





	master = spi_alloc_master(&pdev->dev, sizeof(*spi));

	master = spi_alloc_master(&pdev->dev, sizeof(*spi));

	if (!master)

	if (!master)
@@ -597,7 +559,6 @@ static int mxs_spi_probe(struct platform_device *pdev) 
	ssp->clk = clk;

	ssp->clk = clk;

	ssp->base = base;

	ssp->base = base;

	ssp->devid = devid;

	ssp->devid = devid;

	ssp->dma_channel = dma_channel;





	init_completion(&spi->c);

	init_completion(&spi->c);
@@ -606,10 +567,7 @@ static int mxs_spi_probe(struct platform_device *pdev) 
	if (ret)

	if (ret)

		goto out_master_free;

		goto out_master_free;





	dma_cap_zero(mask);

	ssp->dmach = dma_request_slave_channel(&pdev->dev, "rx-tx");

	dma_cap_set(DMA_SLAVE, mask);

	ssp->dma_data.chan_irq = irq_dma;

	ssp->dmach = dma_request_channel(mask, mxs_ssp_dma_filter, ssp);

	if (!ssp->dmach) {

	if (!ssp->dmach) {

		dev_err(ssp->dev, "Failed to request DMA\n");

		dev_err(ssp->dev, "Failed to request DMA\n");

		goto out_master_free;

		goto out_master_free;

include/linux/spi/mxs-spi.h

+1 −3
Original line number Original line Diff line number Diff line
@@ -24,7 +24,7 @@ 
#ifndef __LINUX_SPI_MXS_SPI_H__

#ifndef __LINUX_SPI_MXS_SPI_H__

#define __LINUX_SPI_MXS_SPI_H__

#define __LINUX_SPI_MXS_SPI_H__





#include <linux/fsl/mxs-dma.h>

#include <linux/dmaengine.h>





#define ssp_is_old(host)	((host)->devid == IMX23_SSP)

#define ssp_is_old(host)	((host)->devid == IMX23_SSP)
@@ -137,9 +137,7 @@ struct mxs_ssp { 
	unsigned int			clk_rate;

	unsigned int			clk_rate;

	enum mxs_ssp_id			devid;

	enum mxs_ssp_id			devid;





	int				dma_channel;

	struct dma_chan			*dmach;

	struct dma_chan			*dmach;

	struct mxs_dma_data		dma_data;

	unsigned int			dma_dir;

	unsigned int			dma_dir;

	enum dma_transfer_direction	slave_dirn;

	enum dma_transfer_direction	slave_dirn;

	u32				ssp_pio_words[SSP_PIO_NUM];

	u32				ssp_pio_words[SSP_PIO_NUM];