Commit 7850cdfc authored by Qipan Li's avatar Qipan Li Committed by Mark Brown
Browse files

spi: sirf: correct spi gpio and hardware chipselect behaviour 



the old codes check the cs-gpios, if the gpio number is 0 like:
<&gpio, 0, 0>, the driver will use the only hardware chipselect.

this is wrong because of_spi_register_master() can read property
cs-gpios from device node and set the spi master's cs number and
gpio cs automatically based on whether the cs-gpios is valid.

this patch fixes the beviour of CSR spi driver and move to a core
level supported way.

Signed-off-by: default avatarQipan Li <Qipan.Li@csr.com>
Signed-off-by: default avatarBarry Song <Baohua.Song@csr.com>
Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent 7d1311b9

drivers/spi/spi-sirf.c

+33 −53
Original line number Diff line number Diff line
@@ -170,8 +170,7 @@ struct sirfsoc_spi { 
	 * command model

	 */

	bool	tx_by_cmd;



	int chipselect[0];

	bool	hw_cs;

};



static void spi_sirfsoc_rx_word_u8(struct sirfsoc_spi *sspi)
@@ -484,7 +483,7 @@ static void spi_sirfsoc_chipselect(struct spi_device *spi, int value) 
{

	struct sirfsoc_spi *sspi = spi_master_get_devdata(spi->master);



	if (sspi->chipselect[spi->chip_select] == 0) {

	if (sspi->hw_cs) {

		u32 regval = readl(sspi->base + SIRFSOC_SPI_CTRL);

		switch (value) {

		case BITBANG_CS_ACTIVE:
@@ -502,14 +501,13 @@ static void spi_sirfsoc_chipselect(struct spi_device *spi, int value) 
		}

		writel(regval, sspi->base + SIRFSOC_SPI_CTRL);

	} else {

		int gpio = sspi->chipselect[spi->chip_select];

		switch (value) {

		case BITBANG_CS_ACTIVE:

			gpio_direction_output(gpio,

			gpio_direction_output(spi->cs_gpio,

					spi->mode & SPI_CS_HIGH ? 1 : 0);

			break;

		case BITBANG_CS_INACTIVE:

			gpio_direction_output(gpio,

			gpio_direction_output(spi->cs_gpio,

					spi->mode & SPI_CS_HIGH ? 0 : 1);

			break;

		}
@@ -603,8 +601,8 @@ spi_sirfsoc_setup_transfer(struct spi_device *spi, struct spi_transfer *t) 
		sspi->tx_by_cmd = false;

	}

	/*

	 * set spi controller in RISC chipselect mode, we are controlling CS by

	 * software BITBANG_CS_ACTIVE and BITBANG_CS_INACTIVE.

	 * it should never set to hardware cs mode because in hardware cs mode,

	 * cs signal can't controlled by driver.

	 */

	regval |= SIRFSOC_SPI_CS_IO_MODE;

	writel(regval, sspi->base + SIRFSOC_SPI_CTRL);
@@ -627,9 +625,17 @@ spi_sirfsoc_setup_transfer(struct spi_device *spi, struct spi_transfer *t) 


static int spi_sirfsoc_setup(struct spi_device *spi)

{

	struct sirfsoc_spi *sspi;



	if (!spi->max_speed_hz)

		return -EINVAL;



	sspi = spi_master_get_devdata(spi->master);



	if (spi->cs_gpio == -ENOENT)

		sspi->hw_cs = true;

	else

		sspi->hw_cs = false;

	return spi_sirfsoc_setup_transfer(spi, NULL);

}
@@ -638,19 +644,10 @@ static int spi_sirfsoc_probe(struct platform_device *pdev) 
	struct sirfsoc_spi *sspi;

	struct spi_master *master;

	struct resource *mem_res;

	int num_cs, cs_gpio, irq;

	int i;

	int ret;

	int irq;

	int i, ret;



	ret = of_property_read_u32(pdev->dev.of_node,

			"sirf,spi-num-chipselects", &num_cs);

	if (ret < 0) {

		dev_err(&pdev->dev, "Unable to get chip select number\n");

		goto err_cs;

	}



	master = spi_alloc_master(&pdev->dev,

			sizeof(*sspi) + sizeof(int) * num_cs);

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

	if (!master) {

		dev_err(&pdev->dev, "Unable to allocate SPI master\n");

		return -ENOMEM;
@@ -658,32 +655,6 @@ static int spi_sirfsoc_probe(struct platform_device *pdev) 
	platform_set_drvdata(pdev, master);

	sspi = spi_master_get_devdata(master);



	master->num_chipselect = num_cs;



	for (i = 0; i < master->num_chipselect; i++) {

		cs_gpio = of_get_named_gpio(pdev->dev.of_node, "cs-gpios", i);

		if (cs_gpio < 0) {

			dev_err(&pdev->dev, "can't get cs gpio from DT\n");

			ret = -ENODEV;

			goto free_master;

		}



		sspi->chipselect[i] = cs_gpio;

		if (cs_gpio == 0)

			continue; /* use cs from spi controller */



		ret = gpio_request(cs_gpio, DRIVER_NAME);

		if (ret) {

			while (i > 0) {

				i--;

				if (sspi->chipselect[i] > 0)

					gpio_free(sspi->chipselect[i]);

			}

			dev_err(&pdev->dev, "fail to request cs gpios\n");

			goto free_master;

		}

	}



	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);

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

	if (IS_ERR(sspi->base)) {
@@ -753,7 +724,21 @@ static int spi_sirfsoc_probe(struct platform_device *pdev) 
	ret = spi_bitbang_start(&sspi->bitbang);

	if (ret)

		goto free_dummypage;



	for (i = 0; master->cs_gpios && i < master->num_chipselect; i++) {

		if (master->cs_gpios[i] == -ENOENT)

			continue;

		if (!gpio_is_valid(master->cs_gpios[i])) {

			dev_err(&pdev->dev, "no valid gpio\n");

			ret = -EINVAL;

			goto free_dummypage;

		}

		ret = devm_gpio_request(&pdev->dev,

				master->cs_gpios[i], DRIVER_NAME);

		if (ret) {

			dev_err(&pdev->dev, "failed to request gpio\n");

			goto free_dummypage;

		}

	}

	dev_info(&pdev->dev, "registerred, bus number = %d\n", master->bus_num);



	return 0;
@@ -768,7 +753,7 @@ free_rx_dma: 
	dma_release_channel(sspi->rx_chan);

free_master:

	spi_master_put(master);

err_cs:



	return ret;

}
@@ -776,16 +761,11 @@ static int spi_sirfsoc_remove(struct platform_device *pdev) 
{

	struct spi_master *master;

	struct sirfsoc_spi *sspi;

	int i;



	master = platform_get_drvdata(pdev);

	sspi = spi_master_get_devdata(master);



	spi_bitbang_stop(&sspi->bitbang);

	for (i = 0; i < master->num_chipselect; i++) {

		if (sspi->chipselect[i] > 0)

			gpio_free(sspi->chipselect[i]);

	}

	kfree(sspi->dummypage);

	clk_disable_unprepare(sspi->clk);

	clk_put(sspi->clk);

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