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-rw-r--r--drivers/i2c/busses/i2c-at91-core.c9
-rw-r--r--drivers/i2c/busses/i2c-at91-master.c30
-rw-r--r--drivers/i2c/busses/i2c-at91.h5
3 files changed, 41 insertions, 3 deletions
diff --git a/drivers/i2c/busses/i2c-at91-core.c b/drivers/i2c/busses/i2c-at91-core.c
index e96360f5571d..1f4ee7eafbc4 100644
--- a/drivers/i2c/busses/i2c-at91-core.c
+++ b/drivers/i2c/busses/i2c-at91-core.c
@@ -69,6 +69,7 @@ static struct at91_twi_pdata at91rm9200_config = {
.has_alt_cmd = false,
.has_hold_field = false,
.has_dig_filtr = false,
+ .has_adv_dig_filtr = false,
};
static struct at91_twi_pdata at91sam9261_config = {
@@ -78,6 +79,7 @@ static struct at91_twi_pdata at91sam9261_config = {
.has_alt_cmd = false,
.has_hold_field = false,
.has_dig_filtr = false,
+ .has_adv_dig_filtr = false,
};
static struct at91_twi_pdata at91sam9260_config = {
@@ -87,6 +89,7 @@ static struct at91_twi_pdata at91sam9260_config = {
.has_alt_cmd = false,
.has_hold_field = false,
.has_dig_filtr = false,
+ .has_adv_dig_filtr = false,
};
static struct at91_twi_pdata at91sam9g20_config = {
@@ -96,6 +99,7 @@ static struct at91_twi_pdata at91sam9g20_config = {
.has_alt_cmd = false,
.has_hold_field = false,
.has_dig_filtr = false,
+ .has_adv_dig_filtr = false,
};
static struct at91_twi_pdata at91sam9g10_config = {
@@ -105,6 +109,7 @@ static struct at91_twi_pdata at91sam9g10_config = {
.has_alt_cmd = false,
.has_hold_field = false,
.has_dig_filtr = false,
+ .has_adv_dig_filtr = false,
};
static const struct platform_device_id at91_twi_devtypes[] = {
@@ -136,6 +141,7 @@ static struct at91_twi_pdata at91sam9x5_config = {
.has_alt_cmd = false,
.has_hold_field = false,
.has_dig_filtr = false,
+ .has_adv_dig_filtr = false,
};
static struct at91_twi_pdata sama5d4_config = {
@@ -145,6 +151,7 @@ static struct at91_twi_pdata sama5d4_config = {
.has_alt_cmd = false,
.has_hold_field = true,
.has_dig_filtr = true,
+ .has_adv_dig_filtr = false,
};
static struct at91_twi_pdata sama5d2_config = {
@@ -154,6 +161,7 @@ static struct at91_twi_pdata sama5d2_config = {
.has_alt_cmd = true,
.has_hold_field = true,
.has_dig_filtr = true,
+ .has_adv_dig_filtr = true,
};
static struct at91_twi_pdata sam9x60_config = {
@@ -163,6 +171,7 @@ static struct at91_twi_pdata sam9x60_config = {
.has_alt_cmd = true,
.has_hold_field = true,
.has_dig_filtr = true,
+ .has_adv_dig_filtr = true,
};
static const struct of_device_id atmel_twi_dt_ids[] = {
diff --git a/drivers/i2c/busses/i2c-at91-master.c b/drivers/i2c/busses/i2c-at91-master.c
index df80557eabfe..273bd8bda32d 100644
--- a/drivers/i2c/busses/i2c-at91-master.c
+++ b/drivers/i2c/busses/i2c-at91-master.c
@@ -43,6 +43,12 @@ 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);
+
+ /* 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 |
+ (AT91_TWI_FILTR_THRES(dev->filter_width) &
+ AT91_TWI_FILTR_THRES_MASK));
}
/*
@@ -51,7 +57,7 @@ void at91_init_twi_bus_master(struct at91_twi_dev *dev)
*/
static void at91_calc_twi_clock(struct at91_twi_dev *dev)
{
- int ckdiv, cdiv, div, hold = 0;
+ int ckdiv, cdiv, div, hold = 0, filter_width = 0;
struct at91_twi_pdata *pdata = dev->pdata;
int offset = pdata->clk_offset;
int max_ckdiv = pdata->clk_max_div;
@@ -90,11 +96,29 @@ static void at91_calc_twi_clock(struct at91_twi_dev *dev)
}
}
+ if (pdata->has_adv_dig_filtr) {
+ /*
+ * filter width = 0 to AT91_TWI_FILTR_THRES_MAX
+ * peripheral clocks
+ */
+ filter_width = DIV_ROUND_UP(t->digital_filter_width_ns
+ * (clk_get_rate(dev->clk) / 1000), 1000000);
+ if (filter_width > AT91_TWI_FILTR_THRES_MAX) {
+ dev_warn(dev->dev,
+ "Filter threshold set to its maximum value (%d instead of %d)\n",
+ AT91_TWI_FILTR_THRES_MAX, filter_width);
+ filter_width = AT91_TWI_FILTR_THRES_MAX;
+ }
+ }
+
dev->twi_cwgr_reg = (ckdiv << 16) | (cdiv << 8) | cdiv
| AT91_TWI_CWGR_HOLD(hold);
- dev_dbg(dev->dev, "cdiv %d ckdiv %d hold %d (%d ns)\n",
- cdiv, ckdiv, hold, t->sda_hold_ns);
+ dev->filter_width = filter_width;
+
+ dev_dbg(dev->dev, "cdiv %d ckdiv %d hold %d (%d ns), filter_width %d (%d ns)\n",
+ cdiv, ckdiv, hold, t->sda_hold_ns, filter_width,
+ t->digital_filter_width_ns);
}
static void at91_twi_dma_cleanup(struct at91_twi_dev *dev)
diff --git a/drivers/i2c/busses/i2c-at91.h b/drivers/i2c/busses/i2c-at91.h
index c75447ec3acd..d7cf01e32282 100644
--- a/drivers/i2c/busses/i2c-at91.h
+++ b/drivers/i2c/busses/i2c-at91.h
@@ -86,6 +86,9 @@
#define AT91_TWI_FILTR 0x0044
#define AT91_TWI_FILTR_FILT BIT(0)
+#define AT91_TWI_FILTR_THRES(v) ((v) << 8)
+#define AT91_TWI_FILTR_THRES_MAX 7
+#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)
@@ -112,6 +115,7 @@ struct at91_twi_pdata {
bool has_alt_cmd;
bool has_hold_field;
bool has_dig_filtr;
+ bool has_adv_dig_filtr;
struct at_dma_slave dma_slave;
};
@@ -150,6 +154,7 @@ struct at91_twi_dev {
struct i2c_client *slave;
#endif
bool enable_dig_filt;
+ u32 filter_width;
};
unsigned at91_twi_read(struct at91_twi_dev *dev, unsigned reg);