[PATCH v2 09/15] iio: adc: rzg2l_adc: Prepare for the addition of RZ/G3S support

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



From: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>

The ADC IP available on the RZ/G3S differs slightly from the one found on
the RZ/G2L. The identified differences are as follows:
- different number of channels (one being used for temperature conversion);
  consequently, various registers differ
- different default sampling periods
- the RZ/G3S variant lacks the ADVIC register.

To accommodate these differences, the rzg2l_adc driver has been updated by
introducing the struct rzg2l_adc_hw_params, which encapsulates the
hardware-specific differences between the IP variants. A pointer to an
object of type struct rzg2l_adc_hw_params is embedded in
struct rzg2l_adc_data.

Additionally, the completion member of struct rzg2l_adc_data was relocated
to avoid potential padding, if any.

The code has been adjusted to utilize hardware-specific parameters stored
in the new structure instead of relying on plain macros.

The check of chan->channel in rzg2l_adc_read_raw() function, against the
driver specific mask was removed as the subsystem should have already
been done this before reaching the rzg2l_adc_read_raw() function. Along
with it the local variable ch was dropped as chan->channel could be used
instead.

Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
---

Changes in v2:
- kept the RZG2L_ADC_MAX_CHANNELS as suggested in the review process;
  along with it, last_val[] is now again statically alocated; code
  from v1 around last_val has been adjusted to align with the new
  approach
- dropped ch variable from rzg2l_adc_read_raw() and adjusted the
  patch description to reflect it.

 drivers/iio/adc/rzg2l_adc.c | 87 +++++++++++++++++++++++++------------
 1 file changed, 59 insertions(+), 28 deletions(-)

diff --git a/drivers/iio/adc/rzg2l_adc.c b/drivers/iio/adc/rzg2l_adc.c
index c3f9f95cdbba..6740912f83c5 100644
--- a/drivers/iio/adc/rzg2l_adc.c
+++ b/drivers/iio/adc/rzg2l_adc.c
@@ -33,20 +33,15 @@
 #define RZG2L_ADM1_MS			BIT(2)
 #define RZG2L_ADM1_BS			BIT(4)
 #define RZG2L_ADM1_EGA_MASK		GENMASK(13, 12)
-#define RZG2L_ADM2_CHSEL_MASK		GENMASK(7, 0)
 #define RZG2L_ADM3_ADIL_MASK		GENMASK(31, 24)
 #define RZG2L_ADM3_ADCMP_MASK		GENMASK(23, 16)
-#define RZG2L_ADM3_ADCMP_E		FIELD_PREP(RZG2L_ADM3_ADCMP_MASK, 0xe)
-#define RZG2L_ADM3_ADSMP_MASK		GENMASK(15, 0)
 
 #define RZG2L_ADINT			0x20
-#define RZG2L_ADINT_INTEN_MASK		GENMASK(7, 0)
 #define RZG2L_ADINT_CSEEN		BIT(16)
 #define RZG2L_ADINT_INTS		BIT(31)
 
 #define RZG2L_ADSTS			0x24
 #define RZG2L_ADSTS_CSEST		BIT(16)
-#define RZG2L_ADSTS_INTST_MASK		GENMASK(7, 0)
 
 #define RZG2L_ADIVC			0x28
 #define RZG2L_ADIVC_DIVADC_MASK		GENMASK(8, 0)
@@ -57,12 +52,27 @@
 #define RZG2L_ADCR(n)			(0x30 + ((n) * 0x4))
 #define RZG2L_ADCR_AD_MASK		GENMASK(11, 0)
 
-#define RZG2L_ADSMP_DEFAULT_SAMPLING	0x578
-
 #define RZG2L_ADC_MAX_CHANNELS		8
-#define RZG2L_ADC_CHN_MASK		0x7
 #define RZG2L_ADC_TIMEOUT		usecs_to_jiffies(1 * 4)
 
+/**
+ * struct rzg2l_adc_hw_params - ADC hardware specific parameters
+ * @default_adsmp: default ADC sampling period (see ADM3 register)
+ * @adsmp_mask: ADC sampling period mask (see ADM3 register)
+ * @adint_inten_mask: conversion end interrupt mask (see ADINT register)
+ * @default_adcmp: default ADC cmp (see ADM3 register)
+ * @num_channels: number of supported channels
+ * @adivc: specifies if ADVIC register is available
+ */
+struct rzg2l_adc_hw_params {
+	u16 default_adsmp;
+	u16 adsmp_mask;
+	u16 adint_inten_mask;
+	u8 default_adcmp;
+	u8 num_channels;
+	bool adivc;
+};
+
 struct rzg2l_adc_data {
 	const struct iio_chan_spec *channels;
 	u8 num_channels;
@@ -72,8 +82,9 @@ struct rzg2l_adc {
 	void __iomem *base;
 	struct reset_control *presetn;
 	struct reset_control *adrstn;
-	struct completion completion;
 	const struct rzg2l_adc_data *data;
+	const struct rzg2l_adc_hw_params *hw_params;
+	struct completion completion;
 	struct mutex lock;
 	u16 last_val[RZG2L_ADC_MAX_CHANNELS];
 };
@@ -154,6 +165,7 @@ static void rzg2l_set_trigger(struct rzg2l_adc *adc)
 
 static int rzg2l_adc_conversion_setup(struct rzg2l_adc *adc, u8 ch)
 {
+	const struct rzg2l_adc_hw_params *hw_params = adc->hw_params;
 	u32 reg;
 
 	if (rzg2l_adc_readl(adc, RZG2L_ADM(0)) & RZG2L_ADM0_ADBSY)
@@ -163,7 +175,7 @@ static int rzg2l_adc_conversion_setup(struct rzg2l_adc *adc, u8 ch)
 
 	/* Select analog input channel subjected to conversion. */
 	reg = rzg2l_adc_readl(adc, RZG2L_ADM(2));
-	reg &= ~RZG2L_ADM2_CHSEL_MASK;
+	reg &= ~GENMASK(hw_params->num_channels - 1, 0);
 	reg |= BIT(ch);
 	rzg2l_adc_writel(adc, RZG2L_ADM(2), reg);
 
@@ -175,7 +187,7 @@ static int rzg2l_adc_conversion_setup(struct rzg2l_adc *adc, u8 ch)
 	 */
 	reg = rzg2l_adc_readl(adc, RZG2L_ADINT);
 	reg &= ~RZG2L_ADINT_INTS;
-	reg &= ~RZG2L_ADINT_INTEN_MASK;
+	reg &= ~hw_params->adint_inten_mask;
 	reg |= (RZG2L_ADINT_CSEEN | BIT(ch));
 	rzg2l_adc_writel(adc, RZG2L_ADINT, reg);
 
@@ -184,6 +196,7 @@ static int rzg2l_adc_conversion_setup(struct rzg2l_adc *adc, u8 ch)
 
 static int rzg2l_adc_conversion(struct iio_dev *indio_dev, struct rzg2l_adc *adc, u8 ch)
 {
+	const struct rzg2l_adc_hw_params *hw_params = adc->hw_params;
 	struct device *dev = indio_dev->dev.parent;
 	int ret;
 
@@ -201,7 +214,7 @@ static int rzg2l_adc_conversion(struct iio_dev *indio_dev, struct rzg2l_adc *adc
 
 	if (!wait_for_completion_timeout(&adc->completion, RZG2L_ADC_TIMEOUT)) {
 		rzg2l_adc_writel(adc, RZG2L_ADINT,
-				 rzg2l_adc_readl(adc, RZG2L_ADINT) & ~RZG2L_ADINT_INTEN_MASK);
+				 rzg2l_adc_readl(adc, RZG2L_ADINT) & ~hw_params->adint_inten_mask);
 		ret = -ETIMEDOUT;
 	}
 
@@ -219,7 +232,6 @@ static int rzg2l_adc_read_raw(struct iio_dev *indio_dev,
 {
 	struct rzg2l_adc *adc = iio_priv(indio_dev);
 	int ret;
-	u8 ch;
 
 	switch (mask) {
 	case IIO_CHAN_INFO_RAW: {
@@ -228,12 +240,11 @@ static int rzg2l_adc_read_raw(struct iio_dev *indio_dev,
 
 		guard(mutex)(&adc->lock);
 
-		ch = chan->channel & RZG2L_ADC_CHN_MASK;
-		ret = rzg2l_adc_conversion(indio_dev, adc, ch);
+		ret = rzg2l_adc_conversion(indio_dev, adc, chan->channel);
 		if (ret)
 			return ret;
 
-		*val = adc->last_val[ch];
+		*val = adc->last_val[chan->channel];
 
 		return IIO_VAL_INT;
 	}
@@ -258,6 +269,7 @@ static const struct iio_info rzg2l_adc_iio_info = {
 static irqreturn_t rzg2l_adc_isr(int irq, void *dev_id)
 {
 	struct rzg2l_adc *adc = dev_id;
+	const struct rzg2l_adc_hw_params *hw_params = adc->hw_params;
 	unsigned long intst;
 	u32 reg;
 	int ch;
@@ -270,11 +282,11 @@ static irqreturn_t rzg2l_adc_isr(int irq, void *dev_id)
 		return IRQ_HANDLED;
 	}
 
-	intst = reg & RZG2L_ADSTS_INTST_MASK;
+	intst = reg & GENMASK(hw_params->num_channels - 1, 0);
 	if (!intst)
 		return IRQ_NONE;
 
-	for_each_set_bit(ch, &intst, RZG2L_ADC_MAX_CHANNELS)
+	for_each_set_bit(ch, &intst, hw_params->num_channels)
 		adc->last_val[ch] = rzg2l_adc_readl(adc, RZG2L_ADCR(ch)) & RZG2L_ADCR_AD_MASK;
 
 	/* clear the channel interrupt */
@@ -287,6 +299,7 @@ static irqreturn_t rzg2l_adc_isr(int irq, void *dev_id)
 
 static int rzg2l_adc_parse_properties(struct platform_device *pdev, struct rzg2l_adc *adc)
 {
+	const struct rzg2l_adc_hw_params *hw_params = adc->hw_params;
 	struct iio_chan_spec *chan_array;
 	struct rzg2l_adc_data *data;
 	unsigned int channel;
@@ -302,7 +315,7 @@ static int rzg2l_adc_parse_properties(struct platform_device *pdev, struct rzg2l
 	if (!num_channels)
 		return dev_err_probe(&pdev->dev, -ENODEV, "no channel children\n");
 
-	if (num_channels > RZG2L_ADC_MAX_CHANNELS)
+	if (num_channels > hw_params->num_channels)
 		return dev_err_probe(&pdev->dev, -EINVAL, "num of channel children out of range\n");
 
 	chan_array = devm_kcalloc(&pdev->dev, num_channels, sizeof(*chan_array),
@@ -316,7 +329,7 @@ static int rzg2l_adc_parse_properties(struct platform_device *pdev, struct rzg2l
 		if (ret)
 			return ret;
 
-		if (channel >= RZG2L_ADC_MAX_CHANNELS)
+		if (channel >= hw_params->num_channels)
 			return -EINVAL;
 
 		chan_array[i].type = IIO_VOLTAGE;
@@ -336,6 +349,7 @@ static int rzg2l_adc_parse_properties(struct platform_device *pdev, struct rzg2l
 
 static int rzg2l_adc_hw_init(struct device *dev, struct rzg2l_adc *adc)
 {
+	const struct rzg2l_adc_hw_params *hw_params = adc->hw_params;
 	u32 reg;
 	int ret;
 
@@ -353,11 +367,13 @@ static int rzg2l_adc_hw_init(struct device *dev, struct rzg2l_adc *adc)
 	if (ret)
 		goto exit_hw_init;
 
-	/* Only division by 4 can be set */
-	reg = rzg2l_adc_readl(adc, RZG2L_ADIVC);
-	reg &= ~RZG2L_ADIVC_DIVADC_MASK;
-	reg |= RZG2L_ADIVC_DIVADC_4;
-	rzg2l_adc_writel(adc, RZG2L_ADIVC, reg);
+	if (hw_params->adivc) {
+		/* Only division by 4 can be set */
+		reg = rzg2l_adc_readl(adc, RZG2L_ADIVC);
+		reg &= ~RZG2L_ADIVC_DIVADC_MASK;
+		reg |= RZG2L_ADIVC_DIVADC_4;
+		rzg2l_adc_writel(adc, RZG2L_ADIVC, reg);
+	}
 
 	/*
 	 * Setup AMD3
@@ -368,8 +384,10 @@ static int rzg2l_adc_hw_init(struct device *dev, struct rzg2l_adc *adc)
 	reg = rzg2l_adc_readl(adc, RZG2L_ADM(3));
 	reg &= ~RZG2L_ADM3_ADIL_MASK;
 	reg &= ~RZG2L_ADM3_ADCMP_MASK;
-	reg &= ~RZG2L_ADM3_ADSMP_MASK;
-	reg |= (RZG2L_ADM3_ADCMP_E | RZG2L_ADSMP_DEFAULT_SAMPLING);
+	reg &= ~hw_params->adsmp_mask;
+	reg |= FIELD_PREP(RZG2L_ADM3_ADCMP_MASK, hw_params->default_adcmp) |
+	       hw_params->default_adsmp;
+
 	rzg2l_adc_writel(adc, RZG2L_ADM(3), reg);
 
 exit_hw_init:
@@ -392,6 +410,10 @@ static int rzg2l_adc_probe(struct platform_device *pdev)
 
 	adc = iio_priv(indio_dev);
 
+	adc->hw_params = device_get_match_data(dev);
+	if (!adc->hw_params || adc->hw_params->num_channels > RZG2L_ADC_MAX_CHANNELS)
+		return -EINVAL;
+
 	ret = rzg2l_adc_parse_properties(pdev, adc);
 	if (ret)
 		return ret;
@@ -444,8 +466,17 @@ static int rzg2l_adc_probe(struct platform_device *pdev)
 	return devm_iio_device_register(dev, indio_dev);
 }
 
+static const struct rzg2l_adc_hw_params rzg2l_hw_params = {
+	.num_channels = 8,
+	.default_adcmp = 0xe,
+	.default_adsmp = 0x578,
+	.adsmp_mask = GENMASK(15, 0),
+	.adint_inten_mask = GENMASK(7, 0),
+	.adivc = true
+};
+
 static const struct of_device_id rzg2l_adc_match[] = {
-	{ .compatible = "renesas,rzg2l-adc",},
+	{ .compatible = "renesas,rzg2l-adc", .data = &rzg2l_hw_params },
 	{ /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, rzg2l_adc_match);
-- 
2.39.2





[Index of Archives]     [Device Tree Compilter]     [Device Tree Spec]     [Linux Driver Backports]     [Video for Linux]     [Linux USB Devel]     [Linux PCI Devel]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [XFree86]     [Yosemite Backpacking]


  Powered by Linux