This adds OF support to DaVinci SPI controller to configure platform data through device bindings. Also replaces clk_enable() with of clk_prepare_enable() as well as clk_disable() with clk_disable_unprepare(). Signed-off-by: Murali Karicheri <m-karicheri2@xxxxxx> Reviewed-by : Grant Likely <grant.likely@xxxxxxxxxxxx> --- .../devicetree/bindings/spi/spi-davinci.txt | 51 ++++++++++ drivers/spi/spi-davinci.c | 102 +++++++++++++++++--- 2 files changed, 139 insertions(+), 14 deletions(-) create mode 100644 Documentation/devicetree/bindings/spi/spi-davinci.txt diff --git a/Documentation/devicetree/bindings/spi/spi-davinci.txt b/Documentation/devicetree/bindings/spi/spi-davinci.txt new file mode 100644 index 0000000..a2746c5 --- /dev/null +++ b/Documentation/devicetree/bindings/spi/spi-davinci.txt @@ -0,0 +1,51 @@ +Davinci SPI controller device bindings + +Required properties: +- #address-cells: number of cells required to define a chip select + address on the SPI bus. Should be set to 1. +- #size-cells: should be zero. +- compatible: + - "ti,davinci-spi-v1" for SPI version 1.0 + - "ti,davinci-spi-v2" for SPI version 2.0 +- reg: Offset and length of SPI controller register space +- ti,davinci-spi-num-cs: Number of chip selects +- ti,davinci-spi-intr-line: interrupt line used to connect the SPI + IP to the interrupt controller withn the SoC. Possible values + are 0 and 1. Manual says one of the two possible interrupt + lines can be tied to the interrupt controller. Set this + based on a specifc SoC configuration. +- interrupts: interrupt number offset at the irq parent +- clocks: spi clk phandle + +Example of a NOR flash slave device (n25q032) connected to DaVinci +SPI controller device over the SPI bus. + +spi0:spi@20BF0000 { + #address-cells = <1>; + #size-cells = <0>; + compatible = "ti,davinci-spi-v1"; + reg = <0x20BF0000 0x1000>; + ti,davinci-spi-num-cs = <4>; + ti,davinci-spi-intr-line = <0>; + interrupts = <338>; + clocks = <&clkspi>; + + flash: n25q032@0 { + #address-cells = <1>; + #size-cells = <1>; + compatible = "st,m25p32"; + spi-max-frequency = <25000000>; + reg = <0>; + + partition@0 { + label = "u-boot-spl"; + reg = <0x0 0x80000>; + read-only; + }; + + partition@1 { + label = "test"; + reg = <0x80000 0x380000>; + }; + }; +}; diff --git a/drivers/spi/spi-davinci.c b/drivers/spi/spi-davinci.c index 147dfa8..4d5f166 100644 --- a/drivers/spi/spi-davinci.c +++ b/drivers/spi/spi-davinci.c @@ -28,6 +28,8 @@ #include <linux/dmaengine.h> #include <linux/dma-mapping.h> #include <linux/edma.h> +#include <linux/of.h> +#include <linux/of_device.h> #include <linux/spi/spi.h> #include <linux/spi/spi_bitbang.h> #include <linux/slab.h> @@ -135,7 +137,7 @@ struct davinci_spi { int dma_rx_chnum; int dma_tx_chnum; - struct davinci_spi_platform_data *pdata; + struct davinci_spi_platform_data pdata; void (*get_rx)(u32 rx_data, struct davinci_spi *); u32 (*get_tx)(struct davinci_spi *); @@ -213,7 +215,7 @@ static void davinci_spi_chipselect(struct spi_device *spi, int value) bool gpio_chipsel = false; dspi = spi_master_get_devdata(spi->master); - pdata = dspi->pdata; + pdata = &dspi->pdata; if (pdata->chip_sel && chip_sel < pdata->num_chipselect && pdata->chip_sel[chip_sel] != SPI_INTERN_CS) @@ -392,7 +394,7 @@ static int davinci_spi_setup(struct spi_device *spi) struct davinci_spi_platform_data *pdata; dspi = spi_master_get_devdata(spi->master); - pdata = dspi->pdata; + pdata = &dspi->pdata; /* if bits per word length is zero then set it default 8 */ if (!spi->bits_per_word) @@ -534,7 +536,7 @@ static int davinci_spi_bufs(struct spi_device *spi, struct spi_transfer *t) struct scatterlist sg_rx, sg_tx; dspi = spi_master_get_devdata(spi->master); - pdata = dspi->pdata; + pdata = &dspi->pdata; spicfg = (struct davinci_spi_config *)spi->controller_data; if (!spicfg) spicfg = &davinci_spi_default_cfg; @@ -758,6 +760,70 @@ rx_dma_failed: return r; } +#if defined(CONFIG_OF) +static const struct of_device_id davinci_spi_of_match[] = { + { + .compatible = "ti,davinci-spi-v1", + }, + { + .compatible = "ti,davinci-spi-v2", + .data = (void *)SPI_VERSION_2, + }, + { }, +}; +MODULE_DEVICE_TABLE(of, davini_spi_of_match); + +/** + * spi_davinci_get_pdata - Get platform data from DTS binding + * @pdev: ptr to platform data + * @dspi: ptr to driver data + * + * Parses and populates pdata in dspi from device tree bindings. + * + * NOTE: Not all platform data params are supported currently. + */ +static int spi_davinci_get_pdata(struct platform_device *pdev, + struct davinci_spi *dspi) +{ + struct device_node *node = pdev->dev.of_node; + struct davinci_spi_platform_data *pdata; + unsigned int num_cs, intr_line = 0; + const struct of_device_id *match; + + pdata = &dspi->pdata; + + pdata->version = SPI_VERSION_1; + match = of_match_device(of_match_ptr(davinci_spi_of_match), + &pdev->dev); + if (!match) + return -ENODEV; + + /* match data has the SPI version number for SPI_VERSION_2 */ + if (match->data == (void *)SPI_VERSION_2) + pdata->version = SPI_VERSION_2; + + /* + * default num_cs is 1 and all chipsel are internal to the chip + * indicated by chip_sel being NULL. GPIO based CS is not + * supported yet in DT bindings. + */ + num_cs = 1; + of_property_read_u32(node, "ti,davinci-spi-num-cs", &num_cs); + pdata->num_chipselect = num_cs; + of_property_read_u32(node, "ti,davinci-spi-intr-line", &intr_line); + pdata->intr_line = intr_line; + return 0; +} +#else +#define davinci_spi_of_match NULL +static struct davinci_spi_platform_data + *spi_davinci_get_pdata(struct platform_device *pdev, + struct davinci_spi *dspi) +{ + return -ENODEV; +} +#endif + /** * davinci_spi_probe - probe function for SPI Master Controller * @pdev: platform_device structure which contains plateform specific data @@ -780,12 +846,6 @@ static int __devinit davinci_spi_probe(struct platform_device *pdev) int i = 0, ret = 0; u32 spipc0; - pdata = pdev->dev.platform_data; - if (pdata == NULL) { - ret = -ENODEV; - goto err; - } - master = spi_alloc_master(&pdev->dev, sizeof(struct davinci_spi)); if (master == NULL) { ret = -ENOMEM; @@ -800,6 +860,19 @@ static int __devinit davinci_spi_probe(struct platform_device *pdev) goto free_master; } + if (pdev->dev.platform_data) { + pdata = pdev->dev.platform_data; + dspi->pdata = *pdata; + } else { + /* update dspi pdata with that from the DT */ + ret = spi_davinci_get_pdata(pdev, dspi); + if (ret < 0) + goto free_master; + } + + /* pdata in dspi is now updated and point pdata to that */ + pdata = &dspi->pdata; + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (r == NULL) { ret = -ENOENT; @@ -807,7 +880,6 @@ static int __devinit davinci_spi_probe(struct platform_device *pdev) } dspi->pbase = r->start; - dspi->pdata = pdata; mem = request_mem_region(r->start, resource_size(r), pdev->name); if (mem == NULL) { @@ -843,8 +915,9 @@ static int __devinit davinci_spi_probe(struct platform_device *pdev) ret = -ENODEV; goto put_master; } - clk_enable(dspi->clk); + clk_prepare_enable(dspi->clk); + master->dev.of_node = pdev->dev.of_node; master->bus_num = pdev->id; master->num_chipselect = pdata->num_chipselect; master->setup = davinci_spi_setup; @@ -927,7 +1000,7 @@ free_dma: dma_release_channel(dspi->dma_rx); dma_release_channel(dspi->dma_tx); free_clk: - clk_disable(dspi->clk); + clk_disable_unprepare(dspi->clk); clk_put(dspi->clk); put_master: spi_master_put(master); @@ -963,7 +1036,7 @@ static int __devexit davinci_spi_remove(struct platform_device *pdev) spi_bitbang_stop(&dspi->bitbang); - clk_disable(dspi->clk); + clk_disable_unprepare(dspi->clk); clk_put(dspi->clk); spi_master_put(master); free_irq(dspi->irq, dspi); @@ -978,6 +1051,7 @@ static struct platform_driver davinci_spi_driver = { .driver = { .name = "spi_davinci", .owner = THIS_MODULE, + .of_match_table = davinci_spi_of_match, }, .probe = davinci_spi_probe, .remove = __devexit_p(davinci_spi_remove), -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html