From 8bb986a816148d6e8fbaae23be0fee33d6a1ae3f Mon Sep 17 00:00:00 2001 From: Ganesan Ramalingam Date: Fri, 13 Jul 2012 19:14:23 +0530 Subject: [PATCH] i2c: i2c-ocores: Use reg-shift property Deprecate 'regstep' property and use the standard 'reg-shift' property for register offset shifts. 'regstep' will still be supported as an optional property, but will give a warning when used. Signed-off-by: Ganesan Ramalingam Signed-off-by: Jayachandran C Signed-off-by: Wolfram Sang --- .../devicetree/bindings/i2c/i2c-ocores.txt | 8 +++-- drivers/i2c/busses/i2c-ocores.c | 36 +++++++++++++--------- include/linux/i2c-ocores.h | 2 +- 3 files changed, 29 insertions(+), 17 deletions(-) diff --git a/Documentation/devicetree/bindings/i2c/i2c-ocores.txt b/Documentation/devicetree/bindings/i2c/i2c-ocores.txt index bfec894..1c9334b 100644 --- a/Documentation/devicetree/bindings/i2c/i2c-ocores.txt +++ b/Documentation/devicetree/bindings/i2c/i2c-ocores.txt @@ -4,11 +4,14 @@ Required properties: - compatible : "opencores,i2c-ocores" - reg : bus address start and address range size of device - interrupts : interrupt number -- regstep : size of device registers in bytes - clock-frequency : frequency of bus clock in Hz - #address-cells : should be <1> - #size-cells : should be <0> +Optional properties: +- reg-shift : device register offsets are shifted by this value +- regstep : deprecated, use reg-shift above + Example: i2c0: ocores@a0000000 { @@ -17,9 +20,10 @@ Example: compatible = "opencores,i2c-ocores"; reg = <0xa0000000 0x8>; interrupts = <10>; - regstep = <1>; clock-frequency = <20000000>; + reg-shift = <0>; /* 8 bit registers */ + dummy@60 { compatible = "dummy"; reg = <0x60>; diff --git a/drivers/i2c/busses/i2c-ocores.c b/drivers/i2c/busses/i2c-ocores.c index f6e7ad9..9e0709d 100644 --- a/drivers/i2c/busses/i2c-ocores.c +++ b/drivers/i2c/busses/i2c-ocores.c @@ -25,10 +25,11 @@ #include #include #include +#include struct ocores_i2c { void __iomem *base; - int regstep; + u32 reg_shift; wait_queue_head_t wait; struct i2c_adapter adap; struct i2c_msg *msg; @@ -71,12 +72,12 @@ struct ocores_i2c { static inline void oc_setreg(struct ocores_i2c *i2c, int reg, u8 value) { - iowrite8(value, i2c->base + reg * i2c->regstep); + iowrite8(value, i2c->base + (reg << i2c->reg_shift)); } static inline u8 oc_getreg(struct ocores_i2c *i2c, int reg) { - return ioread8(i2c->base + reg * i2c->regstep); + return ioread8(i2c->base + (reg << i2c->reg_shift)); } static void ocores_process(struct ocores_i2c *i2c) @@ -219,22 +220,29 @@ static struct i2c_adapter ocores_adapter = { static int ocores_i2c_of_probe(struct platform_device *pdev, struct ocores_i2c *i2c) { - const __be32* val; - - val = of_get_property(pdev->dev.of_node, "regstep", NULL); - if (!val) { - dev_err(&pdev->dev, "Missing required parameter 'regstep'\n"); - return -ENODEV; + struct device_node *np = pdev->dev.of_node; + u32 val; + + if (of_property_read_u32(np, "reg-shift", &i2c->reg_shift)) { + /* no 'reg-shift', check for deprecated 'regstep' */ + if (!of_property_read_u32(np, "regstep", &val)) { + if (!is_power_of_2(val)) { + dev_err(&pdev->dev, "invalid regstep %d\n", + val); + return -EINVAL; + } + i2c->reg_shift = ilog2(val); + dev_warn(&pdev->dev, + "regstep property deprecated, use reg-shift\n"); + } } - i2c->regstep = be32_to_cpup(val); - val = of_get_property(pdev->dev.of_node, "clock-frequency", NULL); - if (!val) { + if (of_property_read_u32(np, "clock-frequency", &val)) { dev_err(&pdev->dev, "Missing required parameter 'clock-frequency'\n"); return -ENODEV; } - i2c->clock_khz = be32_to_cpup(val) / 1000; + i2c->clock_khz = val / 1000; return 0; } @@ -277,7 +285,7 @@ static int __devinit ocores_i2c_probe(struct platform_device *pdev) pdata = pdev->dev.platform_data; if (pdata) { - i2c->regstep = pdata->regstep; + i2c->reg_shift = pdata->reg_shift; i2c->clock_khz = pdata->clock_khz; } else { ret = ocores_i2c_of_probe(pdev, i2c); diff --git a/include/linux/i2c-ocores.h b/include/linux/i2c-ocores.h index 4d5e57f..5d95df2 100644 --- a/include/linux/i2c-ocores.h +++ b/include/linux/i2c-ocores.h @@ -12,7 +12,7 @@ #define _LINUX_I2C_OCORES_H struct ocores_i2c_platform_data { - u32 regstep; /* distance between registers */ + u32 reg_shift; /* register offset shift value */ u32 clock_khz; /* input clock in kHz */ u8 num_devices; /* number of devices in the devices list */ struct i2c_board_info const *devices; /* devices connected to the bus */ -- 2.7.4