diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-designware-platdrv.c')
-rw-r--r-- | drivers/i2c/busses/i2c-designware-platdrv.c | 72 |
1 files changed, 57 insertions, 15 deletions
diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c index 35b70a1..d0bdac0 100644 --- a/drivers/i2c/busses/i2c-designware-platdrv.c +++ b/drivers/i2c/busses/i2c-designware-platdrv.c @@ -34,7 +34,7 @@ #include <linux/sched.h> #include <linux/err.h> #include <linux/interrupt.h> -#include <linux/of_i2c.h> +#include <linux/of.h> #include <linux/platform_device.h> #include <linux/pm.h> #include <linux/pm_runtime.h> @@ -53,9 +53,33 @@ static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev) } #ifdef CONFIG_ACPI +static void dw_i2c_acpi_params(struct platform_device *pdev, char method[], + u16 *hcnt, u16 *lcnt, u32 *sda_hold) +{ + struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER }; + acpi_handle handle = ACPI_HANDLE(&pdev->dev); + union acpi_object *obj; + + if (ACPI_FAILURE(acpi_evaluate_object(handle, method, NULL, &buf))) + return; + + obj = (union acpi_object *)buf.pointer; + if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 3) { + const union acpi_object *objs = obj->package.elements; + + *hcnt = (u16)objs[0].integer.value; + *lcnt = (u16)objs[1].integer.value; + if (sda_hold) + *sda_hold = (u32)objs[2].integer.value; + } + + kfree(buf.pointer); +} + static int dw_i2c_acpi_configure(struct platform_device *pdev) { struct dw_i2c_dev *dev = platform_get_drvdata(pdev); + bool fs_mode = dev->master_cfg & DW_IC_CON_SPEED_FAST; if (!ACPI_HANDLE(&pdev->dev)) return -ENODEV; @@ -63,12 +87,24 @@ static int dw_i2c_acpi_configure(struct platform_device *pdev) dev->adapter.nr = -1; dev->tx_fifo_depth = 32; dev->rx_fifo_depth = 32; + + /* + * Try to get SDA hold time and *CNT values from an ACPI method if + * it exists for both supported speed modes. + */ + dw_i2c_acpi_params(pdev, "SSCN", &dev->ss_hcnt, &dev->ss_lcnt, + fs_mode ? NULL : &dev->sda_hold_time); + dw_i2c_acpi_params(pdev, "FMCN", &dev->fs_hcnt, &dev->fs_lcnt, + fs_mode ? &dev->sda_hold_time : NULL); + return 0; } static const struct acpi_device_id dw_i2c_acpi_match[] = { { "INT33C2", 0 }, { "INT33C3", 0 }, + { "INT3432", 0 }, + { "INT3433", 0 }, { "80860F41", 0 }, { } }; @@ -87,13 +123,6 @@ static int dw_i2c_probe(struct platform_device *pdev) struct resource *mem; int irq, r; - /* NOTE: driver uses the static register mapping */ - mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); - if (!mem) { - dev_err(&pdev->dev, "no mem resource?\n"); - return -EINVAL; - } - irq = platform_get_irq(pdev, 0); if (irq < 0) { dev_err(&pdev->dev, "no irq resource?\n"); @@ -104,6 +133,7 @@ static int dw_i2c_probe(struct platform_device *pdev) if (!dev) return -ENOMEM; + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); dev->base = devm_ioremap_resource(&pdev->dev, mem); if (IS_ERR(dev->base)) return PTR_ERR(dev->base); @@ -121,6 +151,16 @@ static int dw_i2c_probe(struct platform_device *pdev) return PTR_ERR(dev->clk); clk_prepare_enable(dev->clk); + if (pdev->dev.of_node) { + u32 ht = 0; + u32 ic_clk = dev->get_clk_rate_khz(dev); + + of_property_read_u32(pdev->dev.of_node, + "i2c-sda-hold-time-ns", &ht); + dev->sda_hold_time = div_u64((u64)ic_clk * ht + 500000, + 1000000); + } + dev->functionality = I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR | @@ -167,8 +207,6 @@ static int dw_i2c_probe(struct platform_device *pdev) dev_err(&pdev->dev, "failure adding adapter\n"); return r; } - of_i2c_register_devices(adap); - acpi_i2c_register_devices(adap); pm_runtime_set_autosuspend_delay(&pdev->dev, 1000); pm_runtime_use_autosuspend(&pdev->dev); @@ -202,7 +240,7 @@ static const struct of_device_id dw_i2c_of_match[] = { MODULE_DEVICE_TABLE(of, dw_i2c_of_match); #endif -#ifdef CONFIG_PM +#ifdef CONFIG_PM_SLEEP static int dw_i2c_suspend(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); @@ -223,27 +261,31 @@ static int dw_i2c_resume(struct device *dev) return 0; } -#endif static SIMPLE_DEV_PM_OPS(dw_i2c_dev_pm_ops, dw_i2c_suspend, dw_i2c_resume); +#define DW_I2C_DEV_PM_OPS (&dw_i2c_dev_pm_ops) +#else +#define DW_I2C_DEV_PM_OPS NULL +#endif /* work with hotplug and coldplug */ MODULE_ALIAS("platform:i2c_designware"); static struct platform_driver dw_i2c_driver = { - .remove = dw_i2c_remove, + .probe = dw_i2c_probe, + .remove = dw_i2c_remove, .driver = { .name = "i2c_designware", .owner = THIS_MODULE, .of_match_table = of_match_ptr(dw_i2c_of_match), .acpi_match_table = ACPI_PTR(dw_i2c_acpi_match), - .pm = &dw_i2c_dev_pm_ops, + .pm = DW_I2C_DEV_PM_OPS, }, }; static int __init dw_i2c_init_driver(void) { - return platform_driver_probe(&dw_i2c_driver, dw_i2c_probe); + return platform_driver_register(&dw_i2c_driver); } subsys_initcall(dw_i2c_init_driver); |