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spi: sirf: correct spi gpio and hardware chipselect behaviour

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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: Qipan Li <Qipan.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Qipan Li 2014-09-02 17:01:01 +08:00 committed by Mark Brown
parent 7d1311b93e
commit 7850cdfc80
1 changed files with 33 additions and 53 deletions
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86
drivers/spi/spi-sirf.c
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@ -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);