In Cygnus SOC touch screen controller registers are shared with ADC and flex timer. Using readl/writel could lead to race condition. So touch screen driver is enhanced to support register access using syscon framework API's to take care of mutually exclusive access. Signed-off-by: Raveendra Padasalagi <raveendra.padasalagi@xxxxxxxxxxxx> Reviewed-by: Ray Jui <ray.jui@xxxxxxxxxxxx> Reviewed-by: Scott Branden <scott.branden@xxxxxxxxxxxx> --- drivers/input/touchscreen/bcm_iproc_tsc.c | 79 +++++++++++++++++-------------- 1 file changed, 44 insertions(+), 35 deletions(-) diff --git a/drivers/input/touchscreen/bcm_iproc_tsc.c b/drivers/input/touchscreen/bcm_iproc_tsc.c index ae460a5c..9957587 100644 --- a/drivers/input/touchscreen/bcm_iproc_tsc.c +++ b/drivers/input/touchscreen/bcm_iproc_tsc.c @@ -23,6 +23,8 @@ #include <linux/io.h> #include <linux/clk.h> #include <linux/serio.h> +#include <linux/mfd/syscon.h> +#include <linux/regmap.h> #define IPROC_TS_NAME "iproc-ts" @@ -88,7 +90,11 @@ #define TS_WIRE_MODE_BIT BIT(1) #define dbg_reg(dev, priv, reg) \ - dev_dbg(dev, "%20s= 0x%08x\n", #reg, readl((priv)->regs + reg)) +do { \ + u32 val; \ + regmap_read(priv->regmap, reg, &val); \ + dev_dbg(dev, "%20s= 0x%08x\n", #reg, val); \ +} while (0) struct tsc_param { /* Each step is 1024 us. Valid 1-256 */ @@ -141,7 +147,7 @@ struct iproc_ts_priv { struct platform_device *pdev; struct input_dev *idev; - void __iomem *regs; + struct regmap *regmap; struct clk *tsc_clk; int pen_status; @@ -196,22 +202,22 @@ static irqreturn_t iproc_touchscreen_interrupt(int irq, void *data) int i; bool needs_sync = false; - intr_status = readl(priv->regs + INTERRUPT_STATUS); - intr_status &= TS_PEN_INTR_MASK | TS_FIFO_INTR_MASK; + regmap_read(priv->regmap, INTERRUPT_STATUS, &intr_status); + intr_status &= (TS_PEN_INTR_MASK | TS_FIFO_INTR_MASK); if (intr_status == 0) return IRQ_NONE; /* Clear all interrupt status bits, write-1-clear */ - writel(intr_status, priv->regs + INTERRUPT_STATUS); - + regmap_write(priv->regmap, INTERRUPT_STATUS, intr_status); /* Pen up/down */ if (intr_status & TS_PEN_INTR_MASK) { - if (readl(priv->regs + CONTROLLER_STATUS) & TS_PEN_DOWN) + regmap_read(priv->regmap, CONTROLLER_STATUS, &priv->pen_status); + if (priv->pen_status & TS_PEN_DOWN) priv->pen_status = PEN_DOWN_STATUS; else priv->pen_status = PEN_UP_STATUS; - input_report_key(priv->idev, BTN_TOUCH, priv->pen_status); + input_report_key(priv->idev, BTN_TOUCH, priv->pen_status); needs_sync = true; dev_dbg(&priv->pdev->dev, @@ -221,7 +227,7 @@ static irqreturn_t iproc_touchscreen_interrupt(int irq, void *data) /* coordinates in FIFO exceed the theshold */ if (intr_status & TS_FIFO_INTR_MASK) { for (i = 0; i < priv->cfg_params.fifo_threshold; i++) { - raw_coordinate = readl(priv->regs + FIFO_DATA); + regmap_read(priv->regmap, FIFO_DATA, &raw_coordinate); if (raw_coordinate == INVALID_COORD) continue; @@ -239,7 +245,7 @@ static irqreturn_t iproc_touchscreen_interrupt(int irq, void *data) x = (x >> 4) & 0x0FFF; y = (y >> 4) & 0x0FFF; - /* adjust x y according to lcd tsc mount angle */ + /* Adjust x y according to LCD tsc mount angle. */ if (priv->cfg_params.invert_x) x = priv->cfg_params.max_x - x; @@ -262,9 +268,10 @@ static irqreturn_t iproc_touchscreen_interrupt(int irq, void *data) static int iproc_ts_start(struct input_dev *idev) { - struct iproc_ts_priv *priv = input_get_drvdata(idev); u32 val; + u32 mask; int error; + struct iproc_ts_priv *priv = input_get_drvdata(idev); /* Enable clock */ error = clk_prepare_enable(priv->tsc_clk); @@ -279,9 +286,10 @@ static int iproc_ts_start(struct input_dev *idev) * FIFO reaches the int_th value, and pen event(up/down) */ val = TS_PEN_INTR_MASK | TS_FIFO_INTR_MASK; - writel(val, priv->regs + INTERRUPT_MASK); + regmap_update_bits(priv->regmap, INTERRUPT_MASK, val, val); - writel(priv->cfg_params.fifo_threshold, priv->regs + INTERRUPT_THRES); + val = priv->cfg_params.fifo_threshold; + regmap_write(priv->regmap, INTERRUPT_THRES, val); /* Initialize control reg1 */ val = 0; @@ -289,26 +297,23 @@ static int iproc_ts_start(struct input_dev *idev) val |= priv->cfg_params.debounce_timeout << DEBOUNCE_TIMEOUT_SHIFT; val |= priv->cfg_params.settling_timeout << SETTLING_TIMEOUT_SHIFT; val |= priv->cfg_params.touch_timeout << TOUCH_TIMEOUT_SHIFT; - writel(val, priv->regs + REGCTL1); + regmap_write(priv->regmap, REGCTL1, val); /* Try to clear all interrupt status */ - val = readl(priv->regs + INTERRUPT_STATUS); - val |= TS_FIFO_INTR_MASK | TS_PEN_INTR_MASK; - writel(val, priv->regs + INTERRUPT_STATUS); + val = TS_FIFO_INTR_MASK | TS_PEN_INTR_MASK; + regmap_update_bits(priv->regmap, INTERRUPT_STATUS, val, val); /* Initialize control reg2 */ - val = readl(priv->regs + REGCTL2); - val |= TS_CONTROLLER_EN_BIT | TS_WIRE_MODE_BIT; - - val &= ~TS_CONTROLLER_AVGDATA_MASK; + val = TS_CONTROLLER_EN_BIT | TS_WIRE_MODE_BIT; val |= priv->cfg_params.average_data << TS_CONTROLLER_AVGDATA_SHIFT; - val &= ~(TS_CONTROLLER_PWR_LDO | /* PWR up LDO */ + mask = (TS_CONTROLLER_AVGDATA_MASK); + mask |= (TS_CONTROLLER_PWR_LDO | /* PWR up LDO */ TS_CONTROLLER_PWR_ADC | /* PWR up ADC */ TS_CONTROLLER_PWR_BGP | /* PWR up BGP */ TS_CONTROLLER_PWR_TS); /* PWR up TS */ - - writel(val, priv->regs + REGCTL2); + mask |= val; + regmap_update_bits(priv->regmap, REGCTL2, mask, val); ts_reg_dump(priv); @@ -320,12 +325,17 @@ static void iproc_ts_stop(struct input_dev *dev) u32 val; struct iproc_ts_priv *priv = input_get_drvdata(dev); - writel(0, priv->regs + INTERRUPT_MASK); /* Disable all interrupts */ + /* + * Disable FIFO int_th and pen event(up/down)Interrupts only + * as the interrupt mask register is shared between ADC, TS and + * flextimer. + */ + val = TS_PEN_INTR_MASK | TS_FIFO_INTR_MASK; + regmap_update_bits(priv->regmap, INTERRUPT_MASK, val, 0); /* Only power down touch screen controller */ - val = readl(priv->regs + REGCTL2); - val |= TS_CONTROLLER_PWR_TS; - writel(val, priv->regs + REGCTL2); + val = TS_CONTROLLER_PWR_TS; + regmap_update_bits(priv->regmap, REGCTL2, val, val); clk_disable(priv->tsc_clk); } @@ -414,7 +424,6 @@ static int iproc_ts_probe(struct platform_device *pdev) { struct iproc_ts_priv *priv; struct input_dev *idev; - struct resource *res; int irq; int error; @@ -422,12 +431,12 @@ static int iproc_ts_probe(struct platform_device *pdev) if (!priv) return -ENOMEM; - /* touchscreen controller memory mapped regs */ - res = platform_get_resource(pdev, IORESOURCE_MEM, 0); - priv->regs = devm_ioremap_resource(&pdev->dev, res); - if (IS_ERR(priv->regs)) { - error = PTR_ERR(priv->regs); - dev_err(&pdev->dev, "unable to map I/O memory: %d\n", error); + /* touchscreen controller memory mapped regs via syscon*/ + priv->regmap = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, + "ts_syscon"); + if (IS_ERR(priv->regmap)) { + error = PTR_ERR(priv->regmap); + dev_err(&pdev->dev, "unable to map I/O memory:%d\n", error); return error; } -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html