Merge branch 'at91-4.19-trunk/i2c' into linux-4.19-at91

Author: cristibirsan

Documentation/devicetree/bindings/i2c/i2c-at91.txt

@@ -3,7 +3,8 @@ I2C for Atmel platforms
 Required properties :
 - compatible : Must be "atmel,at91rm9200-i2c", "atmel,at91sam9261-i2c",
      "atmel,at91sam9260-i2c", "atmel,at91sam9g20-i2c", "atmel,at91sam9g10-i2c",
-     "atmel,at91sam9x5-i2c", "atmel,sama5d4-i2c" or "atmel,sama5d2-i2c"
+     "atmel,at91sam9x5-i2c", "atmel,sama5d4-i2c", "atmel,sama5d2-i2c" or
+     "microchip,sam9x60-i2c"
 - reg: physical base address of the controller and length of memory mapped
      region.
 - interrupts: interrupt number to the cpu.
@@ -19,6 +20,12 @@ Optional properties:
   capable I2C controllers.
 - i2c-sda-hold-time-ns: TWD hold time, only available for "atmel,sama5d4-i2c"
   and "atmel,sama5d2-i2c".
+- enable-dig-filt: Enable the built-in digital filter on the i2c lines,
+  specifically required depending on the hardware PCB/board and if the
+  version of the controller includes it.
+- enable-ana-filt: Enable the built-in analogic filter on the i2c lines,
+  specifically required depending on the hardware PCB/board and if the
+  version of the controller includes it.
 - Child nodes conforming to i2c bus binding
 
 Examples :
@@ -55,6 +62,8 @@ i2c0: i2c@f8034600 {
 	clocks = <&flx0>;
 	atmel,fifo-size = <16>;
 	i2c-sda-hold-time-ns = <336>;
+	enable-dig-filt;
+	enable-ana-filt;
 
 	wm8731: wm8731@1a {
 		compatible = "wm8731";

drivers/i2c/busses/i2c-at91.c

@@ -90,6 +90,13 @@
 #define	AT91_TWI_ACR_DATAL(len)	((len) & 0xff)
 #define	AT91_TWI_ACR_DIR	BIT(8)
 
+#define AT91_TWI_FILTR		0x0044
+#define AT91_TWI_FILTR_FILT	BIT(0)
+#define AT91_TWI_FILTR_PADFEN	BIT(1)
+#define AT91_TWI_FILTR_PADFCFG	BIT(2)
+#define AT91_TWI_FILTR_THRES(v)		((v) << 8)
+#define AT91_TWI_FILTR_THRES_MASK	GENMASK(10, 8)
+
 #define	AT91_TWI_FMR		0x0050	/* FIFO Mode Register */
 #define	AT91_TWI_FMR_TXRDYM(mode)	(((mode) & 0x3) << 0)
 #define	AT91_TWI_FMR_TXRDYM_MASK	(0x3 << 0)
@@ -114,6 +121,9 @@ struct at91_twi_pdata {
 	bool has_unre_flag;
 	bool has_alt_cmd;
 	bool has_hold_field;
+	bool has_dig_filtr;
+	bool has_adv_dig_filtr;
+	bool has_ana_filtr;
 	struct at_dma_slave dma_slave;
 };
 
@@ -146,6 +156,8 @@ struct at91_twi_dev {
 	bool recv_len_abort;
 	u32 fifo_size;
 	struct at91_twi_dma dma;
+	bool enable_dig_filt;
+	bool enable_ana_filt;
 };
 
 static unsigned at91_twi_read(struct at91_twi_dev *dev, unsigned reg)
@@ -176,6 +188,9 @@ static void at91_twi_irq_restore(struct at91_twi_dev *dev)
 
 static void at91_init_twi_bus(struct at91_twi_dev *dev)
 {
+	struct at91_twi_pdata *pdata = dev->pdata;
+	u32 filtr = 0;
+
 	at91_disable_twi_interrupts(dev);
 	at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_SWRST);
 	/* FIFO should be enabled immediately after the software reset */
@@ -184,6 +199,22 @@ static void at91_init_twi_bus(struct at91_twi_dev *dev)
 	at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_MSEN);
 	at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_SVDIS);
 	at91_twi_write(dev, AT91_TWI_CWGR, dev->twi_cwgr_reg);
+
+	/* enable digital filter */
+	if (pdata->has_dig_filtr && dev->enable_dig_filt)
+		filtr |= AT91_TWI_FILTR_FILT;
+
+	/* enable advanced digital filter */
+	if (pdata->has_adv_dig_filtr && dev->enable_dig_filt)
+		filtr |= AT91_TWI_FILTR_FILT |
+			 (AT91_TWI_FILTR_THRES(7) & AT91_TWI_FILTR_THRES_MASK);
+
+	/* enable analog filter */
+	if (pdata->has_ana_filtr && dev->enable_ana_filt)
+		filtr |= AT91_TWI_FILTR_PADFEN | AT91_TWI_FILTR_PADFCFG;
+
+	if (filtr)
+		at91_twi_write(dev, AT91_TWI_FILTR, filtr);
 }
 
 /*
@@ -831,6 +862,9 @@ static struct at91_twi_pdata at91rm9200_config = {
 	.has_unre_flag = true,
 	.has_alt_cmd = false,
 	.has_hold_field = false,
+	.has_dig_filtr = false,
+	.has_adv_dig_filtr = false,
+	.has_ana_filtr = false,
 };
 
 static struct at91_twi_pdata at91sam9261_config = {
@@ -839,6 +873,9 @@ static struct at91_twi_pdata at91sam9261_config = {
 	.has_unre_flag = false,
 	.has_alt_cmd = false,
 	.has_hold_field = false,
+	.has_dig_filtr = false,
+	.has_adv_dig_filtr = false,
+	.has_ana_filtr = false,
 };
 
 static struct at91_twi_pdata at91sam9260_config = {
@@ -847,6 +884,9 @@ static struct at91_twi_pdata at91sam9260_config = {
 	.has_unre_flag = false,
 	.has_alt_cmd = false,
 	.has_hold_field = false,
+	.has_dig_filtr = false,
+	.has_adv_dig_filtr = false,
+	.has_ana_filtr = false,
 };
 
 static struct at91_twi_pdata at91sam9g20_config = {
@@ -855,6 +895,9 @@ static struct at91_twi_pdata at91sam9g20_config = {
 	.has_unre_flag = false,
 	.has_alt_cmd = false,
 	.has_hold_field = false,
+	.has_dig_filtr = false,
+	.has_adv_dig_filtr = false,
+	.has_ana_filtr = false,
 };
 
 static struct at91_twi_pdata at91sam9g10_config = {
@@ -863,6 +906,9 @@ static struct at91_twi_pdata at91sam9g10_config = {
 	.has_unre_flag = false,
 	.has_alt_cmd = false,
 	.has_hold_field = false,
+	.has_dig_filtr = false,
+	.has_adv_dig_filtr = false,
+	.has_ana_filtr = false,
 };
 
 static const struct platform_device_id at91_twi_devtypes[] = {
@@ -893,6 +939,9 @@ static struct at91_twi_pdata at91sam9x5_config = {
 	.has_unre_flag = false,
 	.has_alt_cmd = false,
 	.has_hold_field = false,
+	.has_dig_filtr = false,
+	.has_adv_dig_filtr = false,
+	.has_ana_filtr = false,
 };
 
 static struct at91_twi_pdata sama5d4_config = {
@@ -901,6 +950,9 @@ static struct at91_twi_pdata sama5d4_config = {
 	.has_unre_flag = false,
 	.has_alt_cmd = false,
 	.has_hold_field = true,
+	.has_dig_filtr = true,
+	.has_adv_dig_filtr = false,
+	.has_ana_filtr = false,
 };
 
 static struct at91_twi_pdata sama5d2_config = {
@@ -909,6 +961,20 @@ static struct at91_twi_pdata sama5d2_config = {
 	.has_unre_flag = true,
 	.has_alt_cmd = true,
 	.has_hold_field = true,
+	.has_dig_filtr = true,
+	.has_adv_dig_filtr = true,
+	.has_ana_filtr = true,
+};
+
+static struct at91_twi_pdata sam9x60_config = {
+	.clk_max_div = 7,
+	.clk_offset = 4,
+	.has_unre_flag = true,
+	.has_alt_cmd = true,
+	.has_hold_field = true,
+	.has_dig_filtr = true,
+	.has_adv_dig_filtr = true,
+	.has_ana_filtr = true,
 };
 
 static const struct of_device_id atmel_twi_dt_ids[] = {
@@ -936,6 +1002,9 @@ static const struct of_device_id atmel_twi_dt_ids[] = {
 	}, {
 		.compatible = "atmel,sama5d2-i2c",
 		.data = &sama5d2_config,
+	}, {
+		.compatible = "microchip,sam9x60-i2c",
+		.data = &sam9x60_config,
 	}, {
 		/* sentinel */
 	}
@@ -1105,6 +1174,12 @@ static int at91_twi_probe(struct platform_device *pdev)
 	if (rc)
 		bus_clk_rate = DEFAULT_TWI_CLK_HZ;
 
+	dev->enable_dig_filt = of_property_read_bool(pdev->dev.of_node,
+						     "enable-dig-filt");
+
+	dev->enable_ana_filt = of_property_read_bool(pdev->dev.of_node,
+						     "enable-ana-filt");
+
 	at91_calc_twi_clock(dev, bus_clk_rate);
 	at91_init_twi_bus(dev);