From 839ad403a2d8081a6c15f6fc2836b01919338f3c Mon Sep 17 00:00:00 2001 From: Andrey Shvetsov <andrey.shvetsov@k2l.de> Date: Mon, 12 Feb 2018 12:24:37 +0100 Subject: [PATCH] staging: most: dim2: read clock speed from the device tree This implements reading of the clock speed parameter from the device tree. Signed-off-by: Andrey Shvetsov <andrey.shvetsov@k2l.de> --- Documentation/devicetree/bindings/inic/microchip,inic-dim2.txt | 64 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ hdm-dim2/dim2_hdm.c | 50 +++++++++++++++++++++++++++++++++++++++++++++++++- 2 files changed, 113 insertions(+), 1 deletion(-) create mode 100644 Documentation/devicetree/bindings/inic/microchip,inic-dim2.txt diff --git a/hdm-dim2/dim2_hdm.c b/hdm-dim2/dim2_hdm.c index 2dba917..05e1896 100644 --- a/hdm-dim2/dim2_hdm.c +++ b/hdm-dim2/dim2_hdm.c @@ -698,6 +698,42 @@ static void dma_free(struct mbo *mbo, u32 size) static const struct of_device_id dim2_of_match[]; +static struct { + const char *clock_speed; + u8 clk_speed; +} clk_mt[] = { + { "256fs", CLK_256FS }, + { "512fs", CLK_512FS }, + { "1024fs", CLK_1024FS }, + { "2048fs", CLK_2048FS }, + { "3072fs", CLK_3072FS }, + { "4096fs", CLK_4096FS }, + { "6144fs", CLK_6144FS }, + { "8192fs", CLK_8192FS }, +}; + +/** + * get_dim2_clk_speed - converts string to DIM2 clock speed value + * + * @clock_speed: string in the format "{NUMBER}fs" + * @val: pointer to get one of the CLK_{NUMBER}FS values + * + * By success stores one of the CLK_{NUMBER}FS in the *val and returns 0, + * otherwise returns -EINVAL. + */ +static int get_dim2_clk_speed(const char *clock_speed, u8 *val) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(clk_mt); i++) { + if (!strcmp(clock_speed, clk_mt[i].clock_speed)) { + *val = clk_mt[i].clk_speed; + return 0; + } + } + return -EINVAL; +} + /* * dim2_probe - dim2 probe handler * @pdev: platform device structure @@ -708,6 +744,7 @@ static const struct of_device_id dim2_of_match[]; static int dim2_probe(struct platform_device *pdev) { const struct dim2_platform_data *pdata; + const char *clock_speed; struct dim2_hdm *dev; struct resource *res; int ret, i; @@ -725,7 +762,18 @@ static int dim2_probe(struct platform_device *pdev) platform_set_drvdata(pdev, dev); - dev->clk_speed = CLK_4096FS; + ret = of_property_read_string(pdev->dev.of_node, + "microchip,clock-speed", &clock_speed); + if (ret) { + dev_err(&pdev->dev, "missing dt property clock-speed\n"); + return ret; + } + + ret = get_dim2_clk_speed(clock_speed, &dev->clk_speed); + if (ret) { + dev_err(&pdev->dev, "bad dt property clock-speed\n"); + return ret; + } res = platform_get_resource(pdev, IORESOURCE_MEM, 0); dev->io_base = devm_ioremap_resource(&pdev->dev, res); -- libgit2 0.26.0