Commit dda96713 authored by Eugen Hristev's avatar Eugen Hristev Committed by Wolfram Sang
Browse files

i2c: at91: add support for analog filtering 



Add support for analog filtering for i2c lines.
The sama5d2 and sam9x60 support this feature.

Signed-off-by: default avatarEugen Hristev <eugen.hristev@microchip.com>
Acked-by: default avatarLudovic Desroches <ludovic.desroches@microchip.com>
Reviewed-by: default avatarPeter Rosin <peda@axentia.se>
Signed-off-by: default avatarWolfram Sang <wsa@the-dreams.de>
parent 2be357af

drivers/i2c/busses/i2c-at91-core.c

+9 −0
Original line number Diff line number Diff line
@@ -70,6 +70,7 @@ static struct at91_twi_pdata at91rm9200_config = { 
	.has_hold_field = false,

	.has_dig_filtr = false,

	.has_adv_dig_filtr = false,

	.has_ana_filtr = false,

};



static struct at91_twi_pdata at91sam9261_config = {
@@ -80,6 +81,7 @@ static struct at91_twi_pdata at91sam9261_config = { 
	.has_hold_field = false,

	.has_dig_filtr = false,

	.has_adv_dig_filtr = false,

	.has_ana_filtr = false,

};



static struct at91_twi_pdata at91sam9260_config = {
@@ -90,6 +92,7 @@ static struct at91_twi_pdata at91sam9260_config = { 
	.has_hold_field = false,

	.has_dig_filtr = false,

	.has_adv_dig_filtr = false,

	.has_ana_filtr = false,

};



static struct at91_twi_pdata at91sam9g20_config = {
@@ -100,6 +103,7 @@ static struct at91_twi_pdata at91sam9g20_config = { 
	.has_hold_field = false,

	.has_dig_filtr = false,

	.has_adv_dig_filtr = false,

	.has_ana_filtr = false,

};



static struct at91_twi_pdata at91sam9g10_config = {
@@ -110,6 +114,7 @@ static struct at91_twi_pdata at91sam9g10_config = { 
	.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[] = {
@@ -142,6 +147,7 @@ static struct at91_twi_pdata at91sam9x5_config = { 
	.has_hold_field = false,

	.has_dig_filtr = false,

	.has_adv_dig_filtr = false,

	.has_ana_filtr = false,

};



static struct at91_twi_pdata sama5d4_config = {
@@ -152,6 +158,7 @@ static struct at91_twi_pdata sama5d4_config = { 
	.has_hold_field = true,

	.has_dig_filtr = true,

	.has_adv_dig_filtr = false,

	.has_ana_filtr = false,

};



static struct at91_twi_pdata sama5d2_config = {
@@ -162,6 +169,7 @@ static struct at91_twi_pdata sama5d2_config = { 
	.has_hold_field = true,

	.has_dig_filtr = true,

	.has_adv_dig_filtr = true,

	.has_ana_filtr = true,

};



static struct at91_twi_pdata sam9x60_config = {
@@ -172,6 +180,7 @@ static struct at91_twi_pdata sam9x60_config = { 
	.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[] = {

drivers/i2c/busses/i2c-at91-master.c

+14 −4
Original line number Diff line number Diff line
@@ -32,6 +32,7 @@ 
void at91_init_twi_bus_master(struct at91_twi_dev *dev)

{

	struct at91_twi_pdata *pdata = dev->pdata;

	u32 filtr = 0;



	/* FIFO should be enabled immediately after the software reset */

	if (dev->fifo_size)
@@ -42,13 +43,20 @@ void at91_init_twi_bus_master(struct at91_twi_dev *dev) 


	/* enable digital filter */

	if (pdata->has_dig_filtr && dev->enable_dig_filt)

		at91_twi_write(dev, AT91_TWI_FILTR, AT91_TWI_FILTR_FILT);

		filtr |= AT91_TWI_FILTR_FILT;



	/* enable advanced digital filter */

	if (pdata->has_adv_dig_filtr && dev->enable_dig_filt)

		at91_twi_write(dev, AT91_TWI_FILTR, AT91_TWI_FILTR_FILT |

		filtr |= AT91_TWI_FILTR_FILT |

			 (AT91_TWI_FILTR_THRES(dev->filter_width) &

				AT91_TWI_FILTR_THRES_MASK));

			 AT91_TWI_FILTR_THRES_MASK);



	/* enable analog filter */

	if (pdata->has_ana_filtr && dev->enable_ana_filt)

		filtr |= AT91_TWI_FILTR_PADFEN;



	if (filtr)

		at91_twi_write(dev, AT91_TWI_FILTR, filtr);

}



/*
@@ -826,6 +834,8 @@ int at91_twi_probe_master(struct platform_device *pdev, 
	dev->enable_dig_filt = of_property_read_bool(pdev->dev.of_node,

						     "i2c-digital-filter");



	dev->enable_ana_filt = of_property_read_bool(pdev->dev.of_node,

						     "i2c-analog-filter");

	at91_calc_twi_clock(dev);



	dev->adapter.algo = &at91_twi_algorithm;

drivers/i2c/busses/i2c-at91.h

+3 −0
Original line number Diff line number Diff line
@@ -86,6 +86,7 @@ 


#define AT91_TWI_FILTR		0x0044

#define AT91_TWI_FILTR_FILT	BIT(0)

#define AT91_TWI_FILTR_PADFEN	BIT(1)

#define AT91_TWI_FILTR_THRES(v)		((v) << 8)

#define AT91_TWI_FILTR_THRES_MAX	7

#define AT91_TWI_FILTR_THRES_MASK	GENMASK(10, 8)
@@ -116,6 +117,7 @@ struct at91_twi_pdata { 
	bool has_hold_field;

	bool has_dig_filtr;

	bool has_adv_dig_filtr;

	bool has_ana_filtr;

	struct at_dma_slave dma_slave;

};
@@ -154,6 +156,7 @@ struct at91_twi_dev { 
	struct i2c_client *slave;

#endif

	bool enable_dig_filt;

	bool enable_ana_filt;

	u32 filter_width;

};

CRA Git | Maintained and supported by SUSTech CRA and CCSE