diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-designware-platdrv.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-designware-platdrv.c | 96 |
1 files changed, 72 insertions, 24 deletions
diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c index bc8773333155..a7431150acf7 100644 --- a/drivers/i2c/busses/i2c-designware-platdrv.c +++ b/drivers/i2c/busses/i2c-designware-platdrv.c @@ -30,6 +30,7 @@ #include <linux/delay.h> #include <linux/i2c.h> #include <linux/clk.h> +#include <linux/clk-provider.h> #include <linux/errno.h> #include <linux/sched.h> #include <linux/err.h> @@ -41,6 +42,7 @@ #include <linux/io.h> #include <linux/slab.h> #include <linux/acpi.h> +#include <linux/platform_data/i2c-designware.h> #include "i2c-designware-core.h" static struct i2c_algorithm i2c_dw_algo = { @@ -79,10 +81,7 @@ static void dw_i2c_acpi_params(struct platform_device *pdev, char method[], 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; + const struct acpi_device_id *id; dev->adapter.nr = -1; dev->tx_fifo_depth = 32; @@ -92,14 +91,33 @@ static int dw_i2c_acpi_configure(struct platform_device *pdev) * 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, "SSCN", &dev->ss_hcnt, &dev->ss_lcnt, NULL); dw_i2c_acpi_params(pdev, "FMCN", &dev->fs_hcnt, &dev->fs_lcnt, - fs_mode ? &dev->sda_hold_time : NULL); + &dev->sda_hold_time); + + /* + * Provide a way for Designware I2C host controllers that are not + * based on Intel LPSS to specify their input clock frequency via + * id->driver_data. + */ + id = acpi_match_device(pdev->dev.driver->acpi_match_table, &pdev->dev); + if (id && id->driver_data) + clk_register_fixed_rate(&pdev->dev, dev_name(&pdev->dev), NULL, + CLK_IS_ROOT, id->driver_data); return 0; } +static void dw_i2c_acpi_unconfigure(struct platform_device *pdev) +{ + struct dw_i2c_dev *dev = platform_get_drvdata(pdev); + const struct acpi_device_id *id; + + id = acpi_match_device(pdev->dev.driver->acpi_match_table, &pdev->dev); + if (id && id->driver_data) + clk_unregister(dev->clk); +} + static const struct acpi_device_id dw_i2c_acpi_match[] = { { "INT33C2", 0 }, { "INT33C3", 0 }, @@ -107,6 +125,7 @@ static const struct acpi_device_id dw_i2c_acpi_match[] = { { "INT3433", 0 }, { "80860F41", 0 }, { "808622C1", 0 }, + { "AMD0010", 133 * 1000 * 1000 }, { } }; MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match); @@ -115,6 +134,7 @@ static inline int dw_i2c_acpi_configure(struct platform_device *pdev) { return -ENODEV; } +static inline void dw_i2c_acpi_unconfigure(struct platform_device *pdev) { } #endif static int dw_i2c_probe(struct platform_device *pdev) @@ -122,7 +142,9 @@ static int dw_i2c_probe(struct platform_device *pdev) struct dw_i2c_dev *dev; struct i2c_adapter *adap; struct resource *mem; + struct dw_i2c_platform_data *pdata; int irq, r; + u32 clk_freq, ht = 0; irq = platform_get_irq(pdev, 0); if (irq < 0) { @@ -145,21 +167,14 @@ static int dw_i2c_probe(struct platform_device *pdev) dev->irq = irq; platform_set_drvdata(pdev, dev); - dev->clk = devm_clk_get(&pdev->dev, NULL); - dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz; - - if (IS_ERR(dev->clk)) - 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); + /* fast mode by default because of legacy reasons */ + clk_freq = 400000; + if (ACPI_COMPANION(&pdev->dev)) { + dw_i2c_acpi_configure(pdev); + } else if (pdev->dev.of_node) { 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); of_property_read_u32(pdev->dev.of_node, "i2c-sda-falling-time-ns", @@ -167,6 +182,21 @@ static int dw_i2c_probe(struct platform_device *pdev) of_property_read_u32(pdev->dev.of_node, "i2c-scl-falling-time-ns", &dev->scl_falling_time); + + of_property_read_u32(pdev->dev.of_node, "clock-frequency", + &clk_freq); + + /* Only standard mode at 100kHz and fast mode at 400kHz + * are supported. + */ + if (clk_freq != 100000 && clk_freq != 400000) { + dev_err(&pdev->dev, "Only 100kHz and 400kHz supported"); + return -EINVAL; + } + } else { + pdata = dev_get_platdata(&pdev->dev); + if (pdata) + clk_freq = pdata->i2c_scl_freq; } dev->functionality = @@ -176,12 +206,27 @@ static int dw_i2c_probe(struct platform_device *pdev) I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_I2C_BLOCK; - dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE | - DW_IC_CON_RESTART_EN | DW_IC_CON_SPEED_FAST; + if (clk_freq == 100000) + dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE | + DW_IC_CON_RESTART_EN | DW_IC_CON_SPEED_STD; + else + dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE | + DW_IC_CON_RESTART_EN | DW_IC_CON_SPEED_FAST; - /* Try first if we can configure the device from ACPI */ - r = dw_i2c_acpi_configure(pdev); - if (r) { + dev->clk = devm_clk_get(&pdev->dev, NULL); + dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz; + if (IS_ERR(dev->clk)) + return PTR_ERR(dev->clk); + clk_prepare_enable(dev->clk); + + if (!dev->sda_hold_time && ht) { + u32 ic_clk = dev->get_clk_rate_khz(dev); + + dev->sda_hold_time = div_u64((u64)ic_clk * ht + 500000, + 1000000); + } + + if (!dev->tx_fifo_depth) { u32 param1 = i2c_dw_read_comp_param(dev); dev->tx_fifo_depth = ((param1 >> 16) & 0xff) + 1; @@ -237,6 +282,9 @@ static int dw_i2c_remove(struct platform_device *pdev) pm_runtime_put(&pdev->dev); pm_runtime_disable(&pdev->dev); + if (ACPI_COMPANION(&pdev->dev)) + dw_i2c_acpi_unconfigure(pdev); + return 0; } |