diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-designware-platdrv.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-designware-platdrv.c | 78 |
1 files changed, 76 insertions, 2 deletions
diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c index 9d467fa0e163..b55c730f28cf 100644 --- a/drivers/i2c/busses/i2c-designware-platdrv.c +++ b/drivers/i2c/busses/i2c-designware-platdrv.c @@ -18,6 +18,7 @@ #include <linux/interrupt.h> #include <linux/io.h> #include <linux/kernel.h> +#include <linux/mfd/syscon.h> #include <linux/module.h> #include <linux/of.h> #include <linux/platform_data/i2c-designware.h> @@ -25,6 +26,7 @@ #include <linux/pm.h> #include <linux/pm_runtime.h> #include <linux/property.h> +#include <linux/regmap.h> #include <linux/reset.h> #include <linux/sched.h> #include <linux/slab.h> @@ -58,6 +60,63 @@ MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match); #endif #ifdef CONFIG_OF +#define BT1_I2C_CTL 0x100 +#define BT1_I2C_CTL_ADDR_MASK GENMASK(7, 0) +#define BT1_I2C_CTL_WR BIT(8) +#define BT1_I2C_CTL_GO BIT(31) +#define BT1_I2C_DI 0x104 +#define BT1_I2C_DO 0x108 + +static int bt1_i2c_read(void *context, unsigned int reg, unsigned int *val) +{ + struct dw_i2c_dev *dev = context; + int ret; + + /* + * Note these methods shouldn't ever fail because the system controller + * registers are memory mapped. We check the return value just in case. + */ + ret = regmap_write(dev->sysmap, BT1_I2C_CTL, + BT1_I2C_CTL_GO | (reg & BT1_I2C_CTL_ADDR_MASK)); + if (ret) + return ret; + + return regmap_read(dev->sysmap, BT1_I2C_DO, val); +} + +static int bt1_i2c_write(void *context, unsigned int reg, unsigned int val) +{ + struct dw_i2c_dev *dev = context; + int ret; + + ret = regmap_write(dev->sysmap, BT1_I2C_DI, val); + if (ret) + return ret; + + return regmap_write(dev->sysmap, BT1_I2C_CTL, + BT1_I2C_CTL_GO | BT1_I2C_CTL_WR | (reg & BT1_I2C_CTL_ADDR_MASK)); +} + +static struct regmap_config bt1_i2c_cfg = { + .reg_bits = 32, + .val_bits = 32, + .reg_stride = 4, + .fast_io = true, + .reg_read = bt1_i2c_read, + .reg_write = bt1_i2c_write, + .max_register = DW_IC_COMP_TYPE, +}; + +static int bt1_i2c_request_regs(struct dw_i2c_dev *dev) +{ + dev->sysmap = syscon_node_to_regmap(dev->dev->of_node->parent); + if (IS_ERR(dev->sysmap)) + return PTR_ERR(dev->sysmap); + + dev->map = devm_regmap_init(dev->dev, NULL, dev, &bt1_i2c_cfg); + return PTR_ERR_OR_ZERO(dev->map); +} + #define MSCC_ICPU_CFG_TWI_DELAY 0x0 #define MSCC_ICPU_CFG_TWI_DELAY_ENABLE BIT(0) #define MSCC_ICPU_CFG_TWI_SPIKE_FILTER 0x4 @@ -90,10 +149,16 @@ static int dw_i2c_of_configure(struct platform_device *pdev) static const struct of_device_id dw_i2c_of_match[] = { { .compatible = "snps,designware-i2c", }, { .compatible = "mscc,ocelot-i2c", .data = (void *)MODEL_MSCC_OCELOT }, + { .compatible = "baikal,bt1-sys-i2c", .data = (void *)MODEL_BAIKAL_BT1 }, {}, }; MODULE_DEVICE_TABLE(of, dw_i2c_of_match); #else +static int bt1_i2c_request_regs(struct dw_i2c_dev *dev) +{ + return -ENODEV; +} + static inline int dw_i2c_of_configure(struct platform_device *pdev) { return -ENODEV; @@ -111,10 +176,19 @@ static void dw_i2c_plat_pm_cleanup(struct dw_i2c_dev *dev) static int dw_i2c_plat_request_regs(struct dw_i2c_dev *dev) { struct platform_device *pdev = to_platform_device(dev->dev); + int ret; - dev->base = devm_platform_ioremap_resource(pdev, 0); + switch (dev->flags & MODEL_MASK) { + case MODEL_BAIKAL_BT1: + ret = bt1_i2c_request_regs(dev); + break; + default: + dev->base = devm_platform_ioremap_resource(pdev, 0); + ret = PTR_ERR_OR_ZERO(dev->base); + break; + } - return PTR_ERR_OR_ZERO(dev->base); + return ret; } static int dw_i2c_plat_probe(struct platform_device *pdev) |