pwm: fsl-ftm: Convert to direct regmap API usage

The regmap core supports different endian modes for devices. This patch
convert to direct regmap API usage, preparing to support big endianness
for LS1 SoC.

Using the regmap framework it will be easy to support devices that only
differ in endianness with the same device driver.

Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

drivers/pwm/pwm-fsl-ftm.c

@@ -18,6 +18,7 @@
 #include <linux/of_address.h>
 #include <linux/platform_device.h>
 #include <linux/pwm.h>
+#include <linux/regmap.h>
 #include <linux/slab.h>
 
 #define FTM_SC		0x00
@@ -82,7 +83,7 @@ struct fsl_pwm_chip {
 	unsigned int cnt_select;
 	unsigned int clk_ps;
 
-	void __iomem *base;
+	struct regmap *regmap;
 
 	int period_ns;
 
@@ -218,10 +219,11 @@ static unsigned long fsl_pwm_calculate_duty(struct fsl_pwm_chip *fpc,
 					    unsigned long period_ns,
 					    unsigned long duty_ns)
 {
-	unsigned long long val, duty;
+	unsigned long long duty;
+	u32 val;
 
-	val = readl(fpc->base + FTM_MOD);
-	duty = duty_ns * (val + 1);
+	regmap_read(fpc->regmap, FTM_MOD, &val);
+	duty = (unsigned long long)duty_ns * (val + 1);
 	do_div(duty, period_ns);
 
 	return (unsigned long)duty;
@@ -231,7 +233,7 @@ static int fsl_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 			  int duty_ns, int period_ns)
 {
 	struct fsl_pwm_chip *fpc = to_fsl_chip(chip);
-	u32 val, period, duty;
+	u32 period, duty;
 
 	mutex_lock(&fpc->lock);
 
@@ -256,11 +258,9 @@ static int fsl_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 			return -EINVAL;
 		}
 
-		val = readl(fpc->base + FTM_SC);
-		val &= ~FTM_SC_PS_MASK;
-		val |= fpc->clk_ps;
-		writel(val, fpc->base + FTM_SC);
-		writel(period - 1, fpc->base + FTM_MOD);
+		regmap_update_bits(fpc->regmap, FTM_SC, FTM_SC_PS_MASK,
+				   fpc->clk_ps);
+		regmap_write(fpc->regmap, FTM_MOD, period - 1);
 
 		fpc->period_ns = period_ns;
 	}
@@ -269,8 +269,9 @@ static int fsl_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 
 	duty = fsl_pwm_calculate_duty(fpc, period_ns, duty_ns);
 
-	writel(FTM_CSC_MSB | FTM_CSC_ELSB, fpc->base + FTM_CSC(pwm->hwpwm));
-	writel(duty, fpc->base + FTM_CV(pwm->hwpwm));
+	regmap_write(fpc->regmap, FTM_CSC(pwm->hwpwm),
+		     FTM_CSC_MSB | FTM_CSC_ELSB);
+	regmap_write(fpc->regmap, FTM_CV(pwm->hwpwm), duty);
 
 	return 0;
 }
@@ -282,31 +283,28 @@ static int fsl_pwm_set_polarity(struct pwm_chip *chip,
 	struct fsl_pwm_chip *fpc = to_fsl_chip(chip);
 	u32 val;
 
-	val = readl(fpc->base + FTM_POL);
+	regmap_read(fpc->regmap, FTM_POL, &val);
 
 	if (polarity == PWM_POLARITY_INVERSED)
 		val |= BIT(pwm->hwpwm);
 	else
 		val &= ~BIT(pwm->hwpwm);
 
-	writel(val, fpc->base + FTM_POL);
+	regmap_write(fpc->regmap, FTM_POL, val);
 
 	return 0;
 }
 
 static int fsl_counter_clock_enable(struct fsl_pwm_chip *fpc)
 {
-	u32 val;
 	int ret;
 
 	if (fpc->use_count != 0)
 		return 0;
 
 	/* select counter clock source */
-	val = readl(fpc->base + FTM_SC);
-	val &= ~FTM_SC_CLK_MASK;
-	val |= FTM_SC_CLK(fpc->cnt_select);
-	writel(val, fpc->base + FTM_SC);
+	regmap_update_bits(fpc->regmap, FTM_SC, FTM_SC_CLK_MASK,
+			   FTM_SC_CLK(fpc->cnt_select));
 
 	ret = clk_prepare_enable(fpc->clk[fpc->cnt_select]);
 	if (ret)
@@ -326,13 +324,10 @@ static int fsl_counter_clock_enable(struct fsl_pwm_chip *fpc)
 static int fsl_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
 {
 	struct fsl_pwm_chip *fpc = to_fsl_chip(chip);
-	u32 val;
 	int ret;
 
 	mutex_lock(&fpc->lock);
-	val = readl(fpc->base + FTM_OUTMASK);
-	val &= ~BIT(pwm->hwpwm);
-	writel(val, fpc->base + FTM_OUTMASK);
+	regmap_update_bits(fpc->regmap, FTM_OUTMASK, BIT(pwm->hwpwm), 0);
 
 	ret = fsl_counter_clock_enable(fpc);
 	mutex_unlock(&fpc->lock);
@@ -342,8 +337,6 @@ static int fsl_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
 
 static void fsl_counter_clock_disable(struct fsl_pwm_chip *fpc)
 {
-	u32 val;
-
 	/*
 	 * already disabled, do nothing
 	 */
@@ -355,9 +348,7 @@ static void fsl_counter_clock_disable(struct fsl_pwm_chip *fpc)
 		return;
 
 	/* no users left, disable PWM counter clock */
-	val = readl(fpc->base + FTM_SC);
-	val &= ~FTM_SC_CLK_MASK;
-	writel(val, fpc->base + FTM_SC);
+	regmap_update_bits(fpc->regmap, FTM_SC, FTM_SC_CLK_MASK, 0);
 
 	clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_CNTEN]);
 	clk_disable_unprepare(fpc->clk[fpc->cnt_select]);
@@ -369,14 +360,12 @@ static void fsl_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
 	u32 val;
 
 	mutex_lock(&fpc->lock);
-	val = readl(fpc->base + FTM_OUTMASK);
-	val |= BIT(pwm->hwpwm);
-	writel(val, fpc->base + FTM_OUTMASK);
+	regmap_update_bits(fpc->regmap, FTM_OUTMASK, BIT(pwm->hwpwm),
+			   BIT(pwm->hwpwm));
 
 	fsl_counter_clock_disable(fpc);
 
-	val = readl(fpc->base + FTM_OUTMASK);
-
+	regmap_read(fpc->regmap, FTM_OUTMASK, &val);
 	if ((val & 0xFF) == 0xFF)
 		fpc->period_ns = 0;
 
@@ -401,19 +390,28 @@ static int fsl_pwm_init(struct fsl_pwm_chip *fpc)
 	if (ret)
 		return ret;
 
-	writel(0x00, fpc->base + FTM_CNTIN);
-	writel(0x00, fpc->base + FTM_OUTINIT);
-	writel(0xFF, fpc->base + FTM_OUTMASK);
+	regmap_write(fpc->regmap, FTM_CNTIN, 0x00);
+	regmap_write(fpc->regmap, FTM_OUTINIT, 0x00);
+	regmap_write(fpc->regmap, FTM_OUTMASK, 0xFF);
 
 	clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_SYS]);
 
 	return 0;
 }
 
+static const struct regmap_config fsl_pwm_regmap_config = {
+	.reg_bits = 32,
+	.reg_stride = 4,
+	.val_bits = 32,
+
+	.max_register = FTM_PWMLOAD,
+};
+
 static int fsl_pwm_probe(struct platform_device *pdev)
 {
 	struct fsl_pwm_chip *fpc;
 	struct resource *res;
+	void __iomem *base;
 	int ret;
 
 	fpc = devm_kzalloc(&pdev->dev, sizeof(*fpc), GFP_KERNEL);
@@ -425,9 +423,16 @@ static int fsl_pwm_probe(struct platform_device *pdev)
 	fpc->chip.dev = &pdev->dev;
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	fpc->base = devm_ioremap_resource(&pdev->dev, res);
-	if (IS_ERR(fpc->base))
-		return PTR_ERR(fpc->base);
+	base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	fpc->regmap = devm_regmap_init_mmio_clk(&pdev->dev, NULL, base,
+						&fsl_pwm_regmap_config);
+	if (IS_ERR(fpc->regmap)) {
+		dev_err(&pdev->dev, "regmap init failed\n");
+		return PTR_ERR(fpc->regmap);
+	}
 
 	fpc->clk[FSL_PWM_CLK_SYS] = devm_clk_get(&pdev->dev, "ftm_sys");
 	if (IS_ERR(fpc->clk[FSL_PWM_CLK_SYS])) {