diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-nomadik.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-nomadik.c | 100 |
1 files changed, 92 insertions, 8 deletions
diff --git a/drivers/i2c/busses/i2c-nomadik.c b/drivers/i2c/busses/i2c-nomadik.c index 8b2ffcf45322..650293ff4d62 100644 --- a/drivers/i2c/busses/i2c-nomadik.c +++ b/drivers/i2c/busses/i2c-nomadik.c @@ -26,6 +26,7 @@ #include <linux/platform_data/i2c-nomadik.h> #include <linux/of.h> #include <linux/of_i2c.h> +#include <linux/pinctrl/consumer.h> #define DRIVER_NAME "nmk-i2c" @@ -147,6 +148,10 @@ struct i2c_nmk_client { * @stop: stop condition. * @xfer_complete: acknowledge completion for a I2C message. * @result: controller propogated result. + * @pinctrl: pinctrl handle. + * @pins_default: default state for the pins. + * @pins_idle: idle state for the pins. + * @pins_sleep: sleep state for the pins. * @busy: Busy doing transfer. */ struct nmk_i2c_dev { @@ -160,6 +165,11 @@ struct nmk_i2c_dev { int stop; struct completion xfer_complete; int result; + /* Three pin states - default, idle & sleep */ + struct pinctrl *pinctrl; + struct pinctrl_state *pins_default; + struct pinctrl_state *pins_idle; + struct pinctrl_state *pins_sleep; bool busy; }; @@ -402,8 +412,7 @@ static void setup_i2c_controller(struct nmk_i2c_dev *dev) static int read_i2c(struct nmk_i2c_dev *dev, u16 flags) { u32 status = 0; - u32 mcr; - u32 irq_mask = 0; + u32 mcr, irq_mask; int timeout; mcr = load_i2c_mcr_reg(dev, flags); @@ -472,8 +481,7 @@ static void fill_tx_fifo(struct nmk_i2c_dev *dev, int no_bytes) static int write_i2c(struct nmk_i2c_dev *dev, u16 flags) { u32 status = 0; - u32 mcr; - u32 irq_mask = 0; + u32 mcr, irq_mask; int timeout; mcr = load_i2c_mcr_reg(dev, flags); @@ -636,6 +644,15 @@ static int nmk_i2c_xfer(struct i2c_adapter *i2c_adap, goto out_clk; } + /* Optionaly enable pins to be muxed in and configured */ + if (!IS_ERR(dev->pins_default)) { + status = pinctrl_select_state(dev->pinctrl, + dev->pins_default); + if (status) + dev_err(&dev->adev->dev, + "could not set default pins\n"); + } + status = init_hw(dev); if (status) goto out; @@ -663,6 +680,15 @@ static int nmk_i2c_xfer(struct i2c_adapter *i2c_adap, out: clk_disable_unprepare(dev->clk); out_clk: + /* Optionally let pins go into idle state */ + if (!IS_ERR(dev->pins_idle)) { + status = pinctrl_select_state(dev->pinctrl, + dev->pins_idle); + if (status) + dev_err(&dev->adev->dev, + "could not set pins to idle state\n"); + } + pm_runtime_put_sync(&dev->adev->dev); dev->busy = false; @@ -703,8 +729,7 @@ static irqreturn_t i2c_irq_handler(int irq, void *arg) struct nmk_i2c_dev *dev = arg; u32 tft, rft; u32 count; - u32 misr; - u32 src = 0; + u32 misr, src; /* load Tx FIFO and Rx FIFO threshold values */ tft = readl(dev->virtbase + I2C_TFTR); @@ -857,15 +882,41 @@ static int nmk_i2c_suspend(struct device *dev) { struct amba_device *adev = to_amba_device(dev); struct nmk_i2c_dev *nmk_i2c = amba_get_drvdata(adev); + int ret; if (nmk_i2c->busy) return -EBUSY; + if (!IS_ERR(nmk_i2c->pins_sleep)) { + ret = pinctrl_select_state(nmk_i2c->pinctrl, + nmk_i2c->pins_sleep); + if (ret) + dev_err(dev, "could not set pins to sleep state\n"); + } + return 0; } static int nmk_i2c_resume(struct device *dev) { + struct amba_device *adev = to_amba_device(dev); + struct nmk_i2c_dev *nmk_i2c = amba_get_drvdata(adev); + int ret; + + /* First go to the default state */ + if (!IS_ERR(nmk_i2c->pins_default)) { + ret = pinctrl_select_state(nmk_i2c->pinctrl, + nmk_i2c->pins_default); + if (ret) + dev_err(dev, "could not set pins to default state\n"); + } + /* Then let's idle the pins until the next transfer happens */ + if (!IS_ERR(nmk_i2c->pins_idle)) { + ret = pinctrl_select_state(nmk_i2c->pinctrl, + nmk_i2c->pins_idle); + if (ret) + dev_err(dev, "could not set pins to idle state\n"); + } return 0; } #else @@ -953,6 +1004,40 @@ static int nmk_i2c_probe(struct amba_device *adev, const struct amba_id *id) dev->adev = adev; amba_set_drvdata(adev, dev); + dev->pinctrl = devm_pinctrl_get(&adev->dev); + if (IS_ERR(dev->pinctrl)) { + ret = PTR_ERR(dev->pinctrl); + goto err_pinctrl; + } + + dev->pins_default = pinctrl_lookup_state(dev->pinctrl, + PINCTRL_STATE_DEFAULT); + if (IS_ERR(dev->pins_default)) { + dev_err(&adev->dev, "could not get default pinstate\n"); + } else { + ret = pinctrl_select_state(dev->pinctrl, + dev->pins_default); + if (ret) + dev_dbg(&adev->dev, "could not set default pinstate\n"); + } + + dev->pins_idle = pinctrl_lookup_state(dev->pinctrl, + PINCTRL_STATE_IDLE); + if (IS_ERR(dev->pins_idle)) { + dev_dbg(&adev->dev, "could not get idle pinstate\n"); + } else { + /* If possible, let's go to idle until the first transfer */ + ret = pinctrl_select_state(dev->pinctrl, + dev->pins_idle); + if (ret) + dev_dbg(&adev->dev, "could not set idle pinstate\n"); + } + + dev->pins_sleep = pinctrl_lookup_state(dev->pinctrl, + PINCTRL_STATE_SLEEP); + if (IS_ERR(dev->pins_sleep)) + dev_dbg(&adev->dev, "could not get sleep pinstate\n"); + dev->virtbase = ioremap(adev->res.start, resource_size(&adev->res)); if (!dev->virtbase) { ret = -ENOMEM; @@ -1020,8 +1105,8 @@ static int nmk_i2c_probe(struct amba_device *adev, const struct amba_id *id) err_irq: iounmap(dev->virtbase); err_no_ioremap: - amba_set_drvdata(adev, NULL); kfree(dev); + err_pinctrl: err_no_mem: return ret; @@ -1044,7 +1129,6 @@ static int nmk_i2c_remove(struct amba_device *adev) release_mem_region(res->start, resource_size(res)); clk_put(dev->clk); pm_runtime_disable(&adev->dev); - amba_set_drvdata(adev, NULL); kfree(dev); return 0; |