diff options
author | Qipan Li <Qipan.Li@csr.com> | 2014-09-02 11:01:01 +0200 |
---|---|---|
committer | Mark Brown <broonie@kernel.org> | 2014-09-04 21:20:15 +0200 |
commit | 7850cdfc8028cc7d522c032f64c62c1c01e85875 (patch) | |
tree | fe03078fee1cc8700136b73f46a4abd71c823efd /drivers/spi | |
parent | Linux 3.17-rc1 (diff) | |
download | linux-7850cdfc8028cc7d522c032f64c62c1c01e85875.tar.xz linux-7850cdfc8028cc7d522c032f64c62c1c01e85875.zip |
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: Qipan Li <Qipan.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi')
-rw-r--r-- | drivers/spi/spi-sirf.c | 86 |
1 files changed, 33 insertions, 53 deletions
diff --git a/drivers/spi/spi-sirf.c b/drivers/spi/spi-sirf.c index 95ac276eaafe..44ec3bbbf5a4 100644 --- a/drivers/spi/spi-sirf.c +++ b/drivers/spi/spi-sirf.c @@ -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; - - 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; - } + int irq; + int i, ret; - 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); |