diff options
Diffstat (limited to 'drivers/regulator/wm831x-dcdc.c')
| -rw-r--r-- | drivers/regulator/wm831x-dcdc.c | 207 |
1 files changed, 189 insertions, 18 deletions
diff --git a/drivers/regulator/wm831x-dcdc.c b/drivers/regulator/wm831x-dcdc.c index 2eefc1a0cf0..0a6577577e8 100644 --- a/drivers/regulator/wm831x-dcdc.c +++ b/drivers/regulator/wm831x-dcdc.c @@ -19,6 +19,8 @@ #include <linux/i2c.h> #include <linux/platform_device.h> #include <linux/regulator/driver.h> +#include <linux/regulator/machine.h> +#include <linux/gpio.h> #include <linux/mfd/wm831x/core.h> #include <linux/mfd/wm831x/regulator.h> @@ -39,6 +41,7 @@ #define WM831X_DCDC_CONTROL_2 1 #define WM831X_DCDC_ON_CONFIG 2 #define WM831X_DCDC_SLEEP_CONTROL 3 +#define WM831X_DCDC_DVS_CONTROL 4 /* * Shared @@ -50,6 +53,10 @@ struct wm831x_dcdc { int base; struct wm831x *wm831x; struct regulator_dev *regulator; + int dvs_gpio; + int dvs_gpio_state; + int on_vsel; + int dvs_vsel; }; static int wm831x_dcdc_is_enabled(struct regulator_dev *rdev) @@ -240,11 +247,9 @@ static int wm831x_buckv_list_voltage(struct regulator_dev *rdev, return -EINVAL; } -static int wm831x_buckv_set_voltage_int(struct regulator_dev *rdev, int reg, - int min_uV, int max_uV) +static int wm831x_buckv_select_min_voltage(struct regulator_dev *rdev, + int min_uV, int max_uV) { - struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev); - struct wm831x *wm831x = dcdc->wm831x; u16 vsel; if (min_uV < 600000) @@ -257,39 +262,126 @@ static int wm831x_buckv_set_voltage_int(struct regulator_dev *rdev, int reg, if (wm831x_buckv_list_voltage(rdev, vsel) > max_uV) return -EINVAL; - return wm831x_set_bits(wm831x, reg, WM831X_DC1_ON_VSEL_MASK, vsel); + return vsel; +} + +static int wm831x_buckv_select_max_voltage(struct regulator_dev *rdev, + int min_uV, int max_uV) +{ + u16 vsel; + + if (max_uV < 600000 || max_uV > 1800000) + return -EINVAL; + + vsel = ((max_uV - 600000) / 12500) + 8; + + if (wm831x_buckv_list_voltage(rdev, vsel) < min_uV || + wm831x_buckv_list_voltage(rdev, vsel) < max_uV) + return -EINVAL; + + return vsel; +} + +static int wm831x_buckv_set_dvs(struct regulator_dev *rdev, int state) +{ + struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev); + + if (state == dcdc->dvs_gpio_state) + return 0; + + dcdc->dvs_gpio_state = state; + gpio_set_value(dcdc->dvs_gpio, state); + + /* Should wait for DVS state change to be asserted if we have + * a GPIO for it, for now assume the device is configured + * for the fastest possible transition. + */ + + return 0; } static int wm831x_buckv_set_voltage(struct regulator_dev *rdev, - int min_uV, int max_uV) + int min_uV, int max_uV) { struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev); - u16 reg = dcdc->base + WM831X_DCDC_ON_CONFIG; + struct wm831x *wm831x = dcdc->wm831x; + int on_reg = dcdc->base + WM831X_DCDC_ON_CONFIG; + int dvs_reg = dcdc->base + WM831X_DCDC_DVS_CONTROL; + int vsel, ret; + + vsel = wm831x_buckv_select_min_voltage(rdev, min_uV, max_uV); + if (vsel < 0) + return vsel; + + /* If this value is already set then do a GPIO update if we can */ + if (dcdc->dvs_gpio && dcdc->on_vsel == vsel) + return wm831x_buckv_set_dvs(rdev, 0); + + if (dcdc->dvs_gpio && dcdc->dvs_vsel == vsel) + return wm831x_buckv_set_dvs(rdev, 1); + + /* Always set the ON status to the minimum voltage */ + ret = wm831x_set_bits(wm831x, on_reg, WM831X_DC1_ON_VSEL_MASK, vsel); + if (ret < 0) + return ret; + dcdc->on_vsel = vsel; + + if (!dcdc->dvs_gpio) + return ret; + + /* Kick the voltage transition now */ + ret = wm831x_buckv_set_dvs(rdev, 0); + if (ret < 0) + return ret; + + /* Set the high voltage as the DVS voltage. This is optimised + * for CPUfreq usage, most processors will keep the maximum + * voltage constant and lower the minimum with the frequency. */ + vsel = wm831x_buckv_select_max_voltage(rdev, min_uV, max_uV); + if (vsel < 0) { + /* This should never happen - at worst the same vsel + * should be chosen */ + WARN_ON(vsel < 0); + return 0; + } + + /* Don't bother if it's the same VSEL we're already using */ + if (vsel == dcdc->on_vsel) + return 0; - return wm831x_buckv_set_voltage_int(rdev, reg, min_uV, max_uV); + ret = wm831x_set_bits(wm831x, dvs_reg, WM831X_DC1_DVS_VSEL_MASK, vsel); + if (ret == 0) + dcdc->dvs_vsel = vsel; + else + dev_warn(wm831x->dev, "Failed to set DCDC DVS VSEL: %d\n", + ret); + + return 0; } static int wm831x_buckv_set_suspend_voltage(struct regulator_dev *rdev, - int uV) + int uV) { struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev); + struct wm831x *wm831x = dcdc->wm831x; u16 reg = dcdc->base + WM831X_DCDC_SLEEP_CONTROL; + int vsel; + + vsel = wm831x_buckv_select_min_voltage(rdev, uV, uV); + if (vsel < 0) + return vsel; - return wm831x_buckv_set_voltage_int(rdev, reg, uV, uV); + return wm831x_set_bits(wm831x, reg, WM831X_DC1_SLP_VSEL_MASK, vsel); } static int wm831x_buckv_get_voltage(struct regulator_dev *rdev) { struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev); - struct wm831x *wm831x = dcdc->wm831x; - u16 reg = dcdc->base + WM831X_DCDC_ON_CONFIG; - int val; - val = wm831x_reg_read(wm831x, reg); - if (val < 0) - return val; - - return wm831x_buckv_list_voltage(rdev, val & WM831X_DC1_ON_VSEL_MASK); + if (dcdc->dvs_gpio && dcdc->dvs_gpio_state) + return wm831x_buckv_list_voltage(rdev, dcdc->dvs_vsel); + else + return wm831x_buckv_list_voltage(rdev, dcdc->on_vsel); } /* Current limit options */ @@ -346,6 +438,64 @@ static struct regulator_ops wm831x_buckv_ops = { .set_suspend_mode = wm831x_dcdc_set_suspend_mode, }; +/* + * Set up DVS control. We just log errors since we can still run + * (with reduced performance) if we fail. + */ +static __devinit void wm831x_buckv_dvs_init(struct wm831x_dcdc *dcdc, + struct wm831x_buckv_pdata *pdata) +{ + struct wm831x *wm831x = dcdc->wm831x; + int ret; + u16 ctrl; + + if (!pdata || !pdata->dvs_gpio) + return; + + switch (pdata->dvs_control_src) { + case 1: + ctrl = 2 << WM831X_DC1_DVS_SRC_SHIFT; + break; + case 2: + ctrl = 3 << WM831X_DC1_DVS_SRC_SHIFT; + break; + default: + dev_err(wm831x->dev, "Invalid DVS control source %d for %s\n", + pdata->dvs_control_src, dcdc->name); + return; + } + + ret = wm831x_set_bits(wm831x, dcdc->base + WM831X_DCDC_DVS_CONTROL, + WM831X_DC1_DVS_SRC_MASK, ctrl); + if (ret < 0) { + dev_err(wm831x->dev, "Failed to set %s DVS source: %d\n", + dcdc->name, ret); + return; + } + + ret = gpio_request(pdata->dvs_gpio, "DCDC DVS"); + if (ret < 0) { + dev_err(wm831x->dev, "Failed to get %s DVS GPIO: %d\n", + dcdc->name, ret); + return; + } + + /* gpiolib won't let us read the GPIO status so pick the higher + * of the two existing voltages so we take it as platform data. + */ + dcdc->dvs_gpio_state = pdata->dvs_init_state; + + ret = gpio_direction_output(pdata->dvs_gpio, dcdc->dvs_gpio_state); + if (ret < 0) { + dev_err(wm831x->dev, "Failed to enable %s DVS GPIO: %d\n", + dcdc->name, ret); + gpio_free(pdata->dvs_gpio); + return; + } + + dcdc->dvs_gpio = pdata->dvs_gpio; +} + static __devinit int wm831x_buckv_probe(struct platform_device *pdev) { struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent); @@ -384,6 +534,23 @@ static __devinit int wm831x_buckv_probe(struct platform_device *pdev) dcdc->desc.ops = &wm831x_buckv_ops; dcdc->desc.owner = THIS_MODULE; + ret = wm831x_reg_read(wm831x, dcdc->base + WM831X_DCDC_ON_CONFIG); + if (ret < 0) { + dev_err(wm831x->dev, "Failed to read ON VSEL: %d\n", ret); + goto err; + } + dcdc->on_vsel = ret & WM831X_DC1_ON_VSEL_MASK; + + ret = wm831x_reg_read(wm831x, dcdc->base + WM831X_DCDC_ON_CONFIG); + if (ret < 0) { + dev_err(wm831x->dev, "Failed to read DVS VSEL: %d\n", ret); + goto err; + } + dcdc->dvs_vsel = ret & WM831X_DC1_DVS_VSEL_MASK; + + if (pdata->dcdc[id]) + wm831x_buckv_dvs_init(dcdc, pdata->dcdc[id]->driver_data); + dcdc->regulator = regulator_register(&dcdc->desc, &pdev->dev, pdata->dcdc[id], dcdc); if (IS_ERR(dcdc->regulator)) { @@ -422,6 +589,8 @@ err_uv: err_regulator: regulator_unregister(dcdc->regulator); err: + if (dcdc->dvs_gpio) + gpio_free(dcdc->dvs_gpio); kfree(dcdc); return ret; } @@ -434,6 +603,8 @@ static __devexit int wm831x_buckv_remove(struct platform_device *pdev) wm831x_free_irq(wm831x, platform_get_irq_byname(pdev, "HC"), dcdc); wm831x_free_irq(wm831x, platform_get_irq_byname(pdev, "UV"), dcdc); regulator_unregister(dcdc->regulator); + if (dcdc->dvs_gpio) + gpio_free(dcdc->dvs_gpio); kfree(dcdc); return 0; |