2019-09-11 08:26:42

by Eugen Hristev

[permalink] [raw]
Subject: [PATCH v5 0/9] i2c: add support for filters

From: Eugen Hristev <[email protected]>

Hello,

This series adds support for analog and digital filters for i2c controllers

This series is based on the series:
[PATCH v2 0/9] i2c: at91: filters support for at91 SoCs
and later
[PATCH v4 0/9] i2c: add support for filters
and enhanced to add the bindings for all controllers plus an extra bindings
for the width of the spikes in nanoseconds (digital filters) and cut-off
frequency (analog filters)

First, bindings are created for
'i2c-analog-filter'
'i2c-digital-filter'
'i2c-digital-filter-width-ns'
'i2c-analog-filter-cutoff-frequency'

The support is added in the i2c core to retrieve filter width/cutoff frequency
and add it to the timings structure.
Next, the at91 driver is enhanced for supporting digital filter, advanced
digital filter (with selectable spike width) and the analog filter.

Finally the device tree for two boards are modified to make use of the
new properties.

This series is the result of the comments on the ML in the direction
requested: to make the bindings globally available for i2c drivers.

Changes in v5:
- renamed i2c-filter-width-ns to i2c-digital-filter-width-ns as this
is applicable only to digital filter
- created new binding i2c-digital-filter-width-ns for analog filters.

Changes in v4:
- renamed i2c-ana-filter to i2c-analog-filter
- renamed i2c-dig-filter to i2c-digital-filter

Changes in v3:
- made bindings global for i2c controllers and modified accordingly
- gave up PADFCDF bit because it's a lack in datasheet
- the computation on the width of the spike is based on periph clock as it
is done for hold time.

Changes in v2:
- added device tree bindings and support for enable-ana-filt and
enable-dig-filt
- added the new properties to the DT for sama5d4_xplained/sama5d2_xplained

Eugen Hristev (9):
dt-bindings: i2c: at91: add new compatible
dt-bindings: i2c: add bindings for i2c analog and digital filter
i2c: add support for filters optional properties
i2c: at91: add new platform support for sam9x60
i2c: at91: add support for digital filtering
i2c: at91: add support for advanced digital filtering
i2c: at91: add support for analog filtering
ARM: dts: at91: sama5d2_xplained: add analog and digital filter for
i2c
ARM: dts: at91: sama5d4_xplained: add digital filter for i2c

Documentation/devicetree/bindings/i2c/i2c-at91.txt | 3 +-
Documentation/devicetree/bindings/i2c/i2c.txt | 18 ++++++++
arch/arm/boot/dts/at91-sama5d2_xplained.dts | 6 +++
arch/arm/boot/dts/at91-sama5d4_xplained.dts | 1 +
drivers/i2c/busses/i2c-at91-core.c | 38 +++++++++++++++++
drivers/i2c/busses/i2c-at91-master.c | 49 ++++++++++++++++++++--
drivers/i2c/busses/i2c-at91.h | 13 ++++++
drivers/i2c/i2c-core-base.c | 6 +++
include/linux/i2c.h | 6 +++
9 files changed, 136 insertions(+), 4 deletions(-)

--
2.7.4


2019-09-11 08:26:47

by Eugen Hristev

[permalink] [raw]
Subject: [PATCH v5 3/9] i2c: add support for filters optional properties

From: Eugen Hristev <[email protected]>

i2c-digital-filter-width-ns:
This optional timing property specifies the width of the spikes on the i2c
lines (in ns) that can be filtered out by built-in digital filters which are
embedded in some i2c controllers.
i2c-analog-filter-cutoff-frequency:
This optional timing property specifies the cutoff frequency of a low-pass
analog filter built-in i2c controllers. This low pass filter is used to filter
out high frequency noise on the i2c lines. Specified in Hz.
Include these properties in the timings structure and read them as integers.

Signed-off-by: Eugen Hristev <[email protected]>
---
drivers/i2c/i2c-core-base.c | 6 ++++++
include/linux/i2c.h | 6 ++++++
2 files changed, 12 insertions(+)

diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index 9c440fa..c9fcb16 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -1658,6 +1658,12 @@ void i2c_parse_fw_timings(struct device *dev, struct i2c_timings *t, bool use_de
t->sda_fall_ns = t->scl_fall_ns;

device_property_read_u32(dev, "i2c-sda-hold-time-ns", &t->sda_hold_ns);
+
+ device_property_read_u32(dev, "i2c-digital-filter-width-ns",
+ &t->digital_filter_width_ns);
+
+ device_property_read_u32(dev, "i2c-analog-filter-cutoff-frequency",
+ &t->analog_filter_cutoff_freq_hz);
}
EXPORT_SYMBOL_GPL(i2c_parse_fw_timings);

diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index fa5552c..26ce143 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -575,6 +575,10 @@ struct i2c_lock_operations {
* @scl_int_delay_ns: time IP core additionally needs to setup SCL in ns
* @sda_fall_ns: time SDA signal takes to fall in ns; t(f) in the I2C specification
* @sda_hold_ns: time IP core additionally needs to hold SDA in ns
+ * @digital_filter_width_ns: width in ns of spikes on i2c lines that the IP core
+ * digital filter can filter out
+ * @analog_filter_cutoff_freq_hz: threshold frequency for the low pass IP core
+ analog filter
*/
struct i2c_timings {
u32 bus_freq_hz;
@@ -583,6 +587,8 @@ struct i2c_timings {
u32 scl_int_delay_ns;
u32 sda_fall_ns;
u32 sda_hold_ns;
+ u32 digital_filter_width_ns;
+ u32 analog_filter_cutoff_freq_hz;
};

/**
--
2.7.4

2019-09-11 08:26:59

by Eugen Hristev

[permalink] [raw]
Subject: [PATCH v5 2/9] dt-bindings: i2c: add bindings for i2c analog and digital filter

From: Eugen Hristev <[email protected]>

Some i2c controllers have a built-in digital or analog filter.
This is specifically required depending on the hardware PCB/board.
Some controllers also allow specifying the maximum width of the
spikes that can be filtered for digital filter. The width length can be
specified in nanoseconds.
Analog filters can be configured to have a cutoff frequency (low-pass filter).
This frequency can be specified in Hz.
Added an optional property for such types of analog filters.

Signed-off-by: Eugen Hristev <[email protected]>
---
Documentation/devicetree/bindings/i2c/i2c.txt | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)

diff --git a/Documentation/devicetree/bindings/i2c/i2c.txt b/Documentation/devicetree/bindings/i2c/i2c.txt
index 44efafd..9a53df4 100644
--- a/Documentation/devicetree/bindings/i2c/i2c.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c.txt
@@ -55,6 +55,24 @@ wants to support one of the below features, it should adapt the bindings below.
Number of nanoseconds the SDA signal takes to fall; t(f) in the I2C
specification.

+- i2c-analog-filter
+ Enable analog filter for i2c lines.
+
+- i2c-digital-filter
+ Enable digital filter for i2c lines.
+
+- i2c-digital-filter-width-ns
+ Width of spikes which can be filtered by digital filter
+ (i2c-digital-filter). This width is specified in nanoseconds.
+
+- i2c-analog-filter-cutoff-frequency
+ Frequency that the analog filter (i2c-analog-filter) uses to distinguish
+ which signal to filter. Signal with higher frequency than specified will
+ be filtered out. Only lower frequency will pass (this is applicable to
+ a low-pass analog filter). Typical value should be above the normal
+ i2c bus clock frequency (clock-frequency).
+ Specified in Hz.
+
- interrupts
interrupts used by the device.

--
2.7.4

2019-09-11 08:27:00

by Eugen Hristev

[permalink] [raw]
Subject: [PATCH v5 4/9] i2c: at91: add new platform support for sam9x60

From: Eugen Hristev <[email protected]>

Add new platform data support for the sam9x60 SoC

Signed-off-by: Eugen Hristev <[email protected]>
---
drivers/i2c/busses/i2c-at91-core.c | 11 +++++++++++
1 file changed, 11 insertions(+)

diff --git a/drivers/i2c/busses/i2c-at91-core.c b/drivers/i2c/busses/i2c-at91-core.c
index 435c7d7..caf1846 100644
--- a/drivers/i2c/busses/i2c-at91-core.c
+++ b/drivers/i2c/busses/i2c-at91-core.c
@@ -148,6 +148,14 @@ static struct at91_twi_pdata sama5d2_config = {
.has_hold_field = 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,
+};
+
static const struct of_device_id atmel_twi_dt_ids[] = {
{
.compatible = "atmel,at91rm9200-i2c",
@@ -174,6 +182,9 @@ 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 */
}
};
--
2.7.4

2019-09-11 08:27:02

by Eugen Hristev

[permalink] [raw]
Subject: [PATCH v5 7/9] i2c: at91: add support for analog filtering

From: Eugen Hristev <[email protected]>

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

Signed-off-by: Eugen Hristev <[email protected]>
---
drivers/i2c/busses/i2c-at91-core.c | 9 +++++++++
drivers/i2c/busses/i2c-at91-master.c | 18 ++++++++++++++----
drivers/i2c/busses/i2c-at91.h | 3 +++
3 files changed, 26 insertions(+), 4 deletions(-)

diff --git a/drivers/i2c/busses/i2c-at91-core.c b/drivers/i2c/busses/i2c-at91-core.c
index 1f4ee7e..e13af48 100644
--- a/drivers/i2c/busses/i2c-at91-core.c
+++ b/drivers/i2c/busses/i2c-at91-core.c
@@ -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[] = {
diff --git a/drivers/i2c/busses/i2c-at91-master.c b/drivers/i2c/busses/i2c-at91-master.c
index 273bd8b..6e0b554 100644
--- a/drivers/i2c/busses/i2c-at91-master.c
+++ b/drivers/i2c/busses/i2c-at91-master.c
@@ -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 |
- (AT91_TWI_FILTR_THRES(dev->filter_width) &
- AT91_TWI_FILTR_THRES_MASK));
+ filtr |= AT91_TWI_FILTR_FILT |
+ (AT91_TWI_FILTR_THRES(dev->filter_width) &
+ 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;
diff --git a/drivers/i2c/busses/i2c-at91.h b/drivers/i2c/busses/i2c-at91.h
index d7cf01e3..977a67b 100644
--- a/drivers/i2c/busses/i2c-at91.h
+++ b/drivers/i2c/busses/i2c-at91.h
@@ -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;
};

--
2.7.4

2019-09-11 08:27:24

by Eugen Hristev

[permalink] [raw]
Subject: [PATCH v5 8/9] ARM: dts: at91: sama5d2_xplained: add analog and digital filter for i2c

From: Eugen Hristev <[email protected]>

Add property for analog and digital filter for i2c1 and i2c2 nodes
for sama5d2_xplained

Signed-off-by: Eugen Hristev <[email protected]>
---
arch/arm/boot/dts/at91-sama5d2_xplained.dts | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/arch/arm/boot/dts/at91-sama5d2_xplained.dts b/arch/arm/boot/dts/at91-sama5d2_xplained.dts
index 808e399..9d0a7fb 100644
--- a/arch/arm/boot/dts/at91-sama5d2_xplained.dts
+++ b/arch/arm/boot/dts/at91-sama5d2_xplained.dts
@@ -334,6 +334,9 @@
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_flx4_default>;
atmel,fifo-size = <16>;
+ i2c-analog-filter;
+ i2c-digital-filter;
+ i2c-digital-filter-width-ns = <35>;
status = "okay";
};
};
@@ -342,6 +345,9 @@
dmas = <0>, <0>;
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_i2c1_default>;
+ i2c-analog-filter;
+ i2c-digital-filter;
+ i2c-digital-filter-width-ns = <35>;
status = "okay";

at24@54 {
--
2.7.4

2019-09-11 08:27:34

by Eugen Hristev

[permalink] [raw]
Subject: [PATCH v5 6/9] i2c: at91: add support for advanced digital filtering

From: Eugen Hristev <[email protected]>

Add new platform data support for advanced digital filtering for i2c.
The sama5d2 and sam9x60 support this feature.
This digital filter allows the user to configure the maximum
width of the spikes that can be filtered.

Signed-off-by: Eugen Hristev <[email protected]>
---
drivers/i2c/busses/i2c-at91-core.c | 9 +++++++++
drivers/i2c/busses/i2c-at91-master.c | 30 +++++++++++++++++++++++++++---
drivers/i2c/busses/i2c-at91.h | 5 +++++
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 e96360f..1f4ee7e 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 df80557..273bd8b 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 c75447e..d7cf01e3 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);
--
2.7.4

2019-09-11 08:27:57

by Eugen Hristev

[permalink] [raw]
Subject: [PATCH v5 9/9] ARM: dts: at91: sama5d4_xplained: add digital filter for i2c

From: Eugen Hristev <[email protected]>

Add property for digital filter for i2c0 node sama5d4_xplained

Signed-off-by: Eugen Hristev <[email protected]>
---
arch/arm/boot/dts/at91-sama5d4_xplained.dts | 1 +
1 file changed, 1 insertion(+)

diff --git a/arch/arm/boot/dts/at91-sama5d4_xplained.dts b/arch/arm/boot/dts/at91-sama5d4_xplained.dts
index fdfc37d..924d949 100644
--- a/arch/arm/boot/dts/at91-sama5d4_xplained.dts
+++ b/arch/arm/boot/dts/at91-sama5d4_xplained.dts
@@ -49,6 +49,7 @@
};

i2c0: i2c@f8014000 {
+ i2c-digital-filter;
status = "okay";
};

--
2.7.4

2019-09-11 08:30:26

by Eugen Hristev

[permalink] [raw]
Subject: [PATCH v5 5/9] i2c: at91: add support for digital filtering

From: Eugen Hristev <[email protected]>

Add new platform data support for digital filtering for i2c.
The sama5d4, sama5d2 and sam9x60 support this feature.

Signed-off-by: Eugen Hristev <[email protected]>
---
drivers/i2c/busses/i2c-at91-core.c | 9 +++++++++
drivers/i2c/busses/i2c-at91-master.c | 9 +++++++++
drivers/i2c/busses/i2c-at91.h | 5 +++++
3 files changed, 23 insertions(+)

diff --git a/drivers/i2c/busses/i2c-at91-core.c b/drivers/i2c/busses/i2c-at91-core.c
index caf1846..e96360f 100644
--- a/drivers/i2c/busses/i2c-at91-core.c
+++ b/drivers/i2c/busses/i2c-at91-core.c
@@ -68,6 +68,7 @@ static struct at91_twi_pdata at91rm9200_config = {
.has_unre_flag = true,
.has_alt_cmd = false,
.has_hold_field = false,
+ .has_dig_filtr = false,
};

static struct at91_twi_pdata at91sam9261_config = {
@@ -76,6 +77,7 @@ static struct at91_twi_pdata at91sam9261_config = {
.has_unre_flag = false,
.has_alt_cmd = false,
.has_hold_field = false,
+ .has_dig_filtr = false,
};

static struct at91_twi_pdata at91sam9260_config = {
@@ -84,6 +86,7 @@ static struct at91_twi_pdata at91sam9260_config = {
.has_unre_flag = false,
.has_alt_cmd = false,
.has_hold_field = false,
+ .has_dig_filtr = false,
};

static struct at91_twi_pdata at91sam9g20_config = {
@@ -92,6 +95,7 @@ static struct at91_twi_pdata at91sam9g20_config = {
.has_unre_flag = false,
.has_alt_cmd = false,
.has_hold_field = false,
+ .has_dig_filtr = false,
};

static struct at91_twi_pdata at91sam9g10_config = {
@@ -100,6 +104,7 @@ static struct at91_twi_pdata at91sam9g10_config = {
.has_unre_flag = false,
.has_alt_cmd = false,
.has_hold_field = false,
+ .has_dig_filtr = false,
};

static const struct platform_device_id at91_twi_devtypes[] = {
@@ -130,6 +135,7 @@ static struct at91_twi_pdata at91sam9x5_config = {
.has_unre_flag = false,
.has_alt_cmd = false,
.has_hold_field = false,
+ .has_dig_filtr = false,
};

static struct at91_twi_pdata sama5d4_config = {
@@ -138,6 +144,7 @@ static struct at91_twi_pdata sama5d4_config = {
.has_unre_flag = false,
.has_alt_cmd = false,
.has_hold_field = true,
+ .has_dig_filtr = true,
};

static struct at91_twi_pdata sama5d2_config = {
@@ -146,6 +153,7 @@ static struct at91_twi_pdata sama5d2_config = {
.has_unre_flag = true,
.has_alt_cmd = true,
.has_hold_field = true,
+ .has_dig_filtr = true,
};

static struct at91_twi_pdata sam9x60_config = {
@@ -154,6 +162,7 @@ static struct at91_twi_pdata sam9x60_config = {
.has_unre_flag = true,
.has_alt_cmd = true,
.has_hold_field = true,
+ .has_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 a3fcc35..df80557 100644
--- a/drivers/i2c/busses/i2c-at91-master.c
+++ b/drivers/i2c/busses/i2c-at91-master.c
@@ -31,12 +31,18 @@

void at91_init_twi_bus_master(struct at91_twi_dev *dev)
{
+ struct at91_twi_pdata *pdata = dev->pdata;
+
/* FIFO should be enabled immediately after the software reset */
if (dev->fifo_size)
at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_FIFOEN);
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)
+ at91_twi_write(dev, AT91_TWI_FILTR, AT91_TWI_FILTR_FILT);
}

/*
@@ -793,6 +799,9 @@ int at91_twi_probe_master(struct platform_device *pdev,
dev_info(dev->dev, "Using FIFO (%u data)\n", dev->fifo_size);
}

+ dev->enable_dig_filt = of_property_read_bool(pdev->dev.of_node,
+ "i2c-digital-filter");
+
at91_calc_twi_clock(dev);

dev->adapter.algo = &at91_twi_algorithm;
diff --git a/drivers/i2c/busses/i2c-at91.h b/drivers/i2c/busses/i2c-at91.h
index 499b506..c75447e 100644
--- a/drivers/i2c/busses/i2c-at91.h
+++ b/drivers/i2c/busses/i2c-at91.h
@@ -84,6 +84,9 @@
#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_FMR 0x0050 /* FIFO Mode Register */
#define AT91_TWI_FMR_TXRDYM(mode) (((mode) & 0x3) << 0)
#define AT91_TWI_FMR_TXRDYM_MASK (0x3 << 0)
@@ -108,6 +111,7 @@ struct at91_twi_pdata {
bool has_unre_flag;
bool has_alt_cmd;
bool has_hold_field;
+ bool has_dig_filtr;
struct at_dma_slave dma_slave;
};

@@ -145,6 +149,7 @@ struct at91_twi_dev {
unsigned smr;
struct i2c_client *slave;
#endif
+ bool enable_dig_filt;
};

unsigned at91_twi_read(struct at91_twi_dev *dev, unsigned reg);
--
2.7.4

2019-09-14 23:31:35

by Ludovic Desroches

[permalink] [raw]
Subject: Re: [PATCH v5 0/9] i2c: add support for filters

On Wed, Sep 11, 2019 at 10:24:14AM +0200, Eugen Hristev - M18282 wrote:
> From: Eugen Hristev <[email protected]>
>
> Hello,
>
> This series adds support for analog and digital filters for i2c controllers
>
> This series is based on the series:
> [PATCH v2 0/9] i2c: at91: filters support for at91 SoCs
> and later
> [PATCH v4 0/9] i2c: add support for filters
> and enhanced to add the bindings for all controllers plus an extra bindings
> for the width of the spikes in nanoseconds (digital filters) and cut-off
> frequency (analog filters)
>
> First, bindings are created for
> 'i2c-analog-filter'
> 'i2c-digital-filter'
> 'i2c-digital-filter-width-ns'
> 'i2c-analog-filter-cutoff-frequency'
>
> The support is added in the i2c core to retrieve filter width/cutoff frequency
> and add it to the timings structure.
> Next, the at91 driver is enhanced for supporting digital filter, advanced
> digital filter (with selectable spike width) and the analog filter.
>
> Finally the device tree for two boards are modified to make use of the
> new properties.
>
> This series is the result of the comments on the ML in the direction
> requested: to make the bindings globally available for i2c drivers.
>
> Changes in v5:
> - renamed i2c-filter-width-ns to i2c-digital-filter-width-ns as this
> is applicable only to digital filter
> - created new binding i2c-digital-filter-width-ns for analog filters.

Acked-by: Ludovic Desroches <[email protected]>

for at91 stuff. You can keep it for the future if needed as long as
changes mainly concerned the generic binding.

Regards

Ludovic

>
> Changes in v4:
> - renamed i2c-ana-filter to i2c-analog-filter
> - renamed i2c-dig-filter to i2c-digital-filter
>
> Changes in v3:
> - made bindings global for i2c controllers and modified accordingly
> - gave up PADFCDF bit because it's a lack in datasheet
> - the computation on the width of the spike is based on periph clock as it
> is done for hold time.
>
> Changes in v2:
> - added device tree bindings and support for enable-ana-filt and
> enable-dig-filt
> - added the new properties to the DT for sama5d4_xplained/sama5d2_xplained
>
> Eugen Hristev (9):
> dt-bindings: i2c: at91: add new compatible
> dt-bindings: i2c: add bindings for i2c analog and digital filter
> i2c: add support for filters optional properties
> i2c: at91: add new platform support for sam9x60
> i2c: at91: add support for digital filtering
> i2c: at91: add support for advanced digital filtering
> i2c: at91: add support for analog filtering
> ARM: dts: at91: sama5d2_xplained: add analog and digital filter for
> i2c
> ARM: dts: at91: sama5d4_xplained: add digital filter for i2c
>
> Documentation/devicetree/bindings/i2c/i2c-at91.txt | 3 +-
> Documentation/devicetree/bindings/i2c/i2c.txt | 18 ++++++++
> arch/arm/boot/dts/at91-sama5d2_xplained.dts | 6 +++
> arch/arm/boot/dts/at91-sama5d4_xplained.dts | 1 +
> drivers/i2c/busses/i2c-at91-core.c | 38 +++++++++++++++++
> drivers/i2c/busses/i2c-at91-master.c | 49 ++++++++++++++++++++--
> drivers/i2c/busses/i2c-at91.h | 13 ++++++
> drivers/i2c/i2c-core-base.c | 6 +++
> include/linux/i2c.h | 6 +++
> 9 files changed, 136 insertions(+), 4 deletions(-)
>
> --
> 2.7.4
>

2019-09-17 18:00:06

by Rob Herring (Arm)

[permalink] [raw]
Subject: Re: [PATCH v5 2/9] dt-bindings: i2c: add bindings for i2c analog and digital filter

On Wed, Sep 11, 2019 at 08:24:20AM +0000, [email protected] wrote:
> From: Eugen Hristev <[email protected]>
>
> Some i2c controllers have a built-in digital or analog filter.
> This is specifically required depending on the hardware PCB/board.
> Some controllers also allow specifying the maximum width of the
> spikes that can be filtered for digital filter. The width length can be
> specified in nanoseconds.
> Analog filters can be configured to have a cutoff frequency (low-pass filter).
> This frequency can be specified in Hz.
> Added an optional property for such types of analog filters.
>
> Signed-off-by: Eugen Hristev <[email protected]>
> ---
> Documentation/devicetree/bindings/i2c/i2c.txt | 18 ++++++++++++++++++
> 1 file changed, 18 insertions(+)

Reviewed-by: Rob Herring <[email protected]>

2019-10-07 07:55:09

by Eugen Hristev

[permalink] [raw]
Subject: Re: [PATCH v5 0/9] i2c: add support for filters



On 11.09.2019 11:24, Eugen Hristev - M18282 wrote:
> From: Eugen Hristev <[email protected]>
>
> Hello,
>
> This series adds support for analog and digital filters for i2c controllers
>
> This series is based on the series:
> [PATCH v2 0/9] i2c: at91: filters support for at91 SoCs
> and later
> [PATCH v4 0/9] i2c: add support for filters
> and enhanced to add the bindings for all controllers plus an extra bindings
> for the width of the spikes in nanoseconds (digital filters) and cut-off
> frequency (analog filters)
>
> First, bindings are created for
> 'i2c-analog-filter'
> 'i2c-digital-filter'
> 'i2c-digital-filter-width-ns'
> 'i2c-analog-filter-cutoff-frequency'
>
> The support is added in the i2c core to retrieve filter width/cutoff frequency
> and add it to the timings structure.
> Next, the at91 driver is enhanced for supporting digital filter, advanced
> digital filter (with selectable spike width) and the analog filter.
>
> Finally the device tree for two boards are modified to make use of the
> new properties.
>
> This series is the result of the comments on the ML in the direction
> requested: to make the bindings globally available for i2c drivers.
>
> Changes in v5:
> - renamed i2c-filter-width-ns to i2c-digital-filter-width-ns as this
> is applicable only to digital filter
> - created new binding i2c-digital-filter-width-ns for analog filters.

Hello Wolfram and Peter,

Are you happy with the changes in this version? I haven't heard from you
since this latest update.
I am interested to know if anymore changes are required or maybe we can
move further with this support.

Thanks !
Eugen

>
> Changes in v4:
> - renamed i2c-ana-filter to i2c-analog-filter
> - renamed i2c-dig-filter to i2c-digital-filter
>
> Changes in v3:
> - made bindings global for i2c controllers and modified accordingly
> - gave up PADFCDF bit because it's a lack in datasheet
> - the computation on the width of the spike is based on periph clock as it
> is done for hold time.
>
> Changes in v2:
> - added device tree bindings and support for enable-ana-filt and
> enable-dig-filt
> - added the new properties to the DT for sama5d4_xplained/sama5d2_xplained
>
> Eugen Hristev (9):
> dt-bindings: i2c: at91: add new compatible
> dt-bindings: i2c: add bindings for i2c analog and digital filter
> i2c: add support for filters optional properties
> i2c: at91: add new platform support for sam9x60
> i2c: at91: add support for digital filtering
> i2c: at91: add support for advanced digital filtering
> i2c: at91: add support for analog filtering
> ARM: dts: at91: sama5d2_xplained: add analog and digital filter for
> i2c
> ARM: dts: at91: sama5d4_xplained: add digital filter for i2c
>
> Documentation/devicetree/bindings/i2c/i2c-at91.txt | 3 +-
> Documentation/devicetree/bindings/i2c/i2c.txt | 18 ++++++++
> arch/arm/boot/dts/at91-sama5d2_xplained.dts | 6 +++
> arch/arm/boot/dts/at91-sama5d4_xplained.dts | 1 +
> drivers/i2c/busses/i2c-at91-core.c | 38 +++++++++++++++++
> drivers/i2c/busses/i2c-at91-master.c | 49 ++++++++++++++++++++--
> drivers/i2c/busses/i2c-at91.h | 13 ++++++
> drivers/i2c/i2c-core-base.c | 6 +++
> include/linux/i2c.h | 6 +++
> 9 files changed, 136 insertions(+), 4 deletions(-)
>

2019-10-14 07:03:18

by Eugen Hristev

[permalink] [raw]
Subject: Re: [PATCH v5 0/9] i2c: add support for filters



On 07.10.2019 10:47, Eugen Hristev wrote:
>
>
> On 11.09.2019 11:24, Eugen Hristev - M18282 wrote:
>> From: Eugen Hristev <[email protected]>
>>
>> Hello,
>>
>> This series adds support for analog and digital filters for i2c
>> controllers
>>
>> This series is based on the series:
>> [PATCH v2 0/9] i2c: at91: filters support for at91 SoCs
>> and later
>> [PATCH v4 0/9] i2c: add support for filters
>> and enhanced to add the bindings for all controllers plus an extra
>> bindings
>> for the width of the spikes in nanoseconds (digital filters) and cut-off
>> frequency (analog filters)
>>
>> First, bindings are created for
>> 'i2c-analog-filter'
>> 'i2c-digital-filter'
>> 'i2c-digital-filter-width-ns'
>> 'i2c-analog-filter-cutoff-frequency'
>>
>> The support is added in the i2c core to retrieve filter width/cutoff
>> frequency
>> and add it to the timings structure.
>> Next, the at91 driver is enhanced for supporting digital filter, advanced
>> digital filter (with selectable spike width) and the analog filter.
>>
>> Finally the device tree for two boards are modified to make use of the
>> new properties.
>>
>> This series is the result of the comments on the ML in the direction
>> requested: to make the bindings globally available for i2c drivers.
>>
>> Changes in v5:
>> - renamed i2c-filter-width-ns to i2c-digital-filter-width-ns as this
>> is applicable only to digital filter
>> - created new binding i2c-digital-filter-width-ns for analog filters.
>
> Hello Wolfram and Peter,
>
> Are you happy with the changes in this version? I haven't heard from you
> since this latest update.
> I am interested to know if anymore changes are required or maybe we can
> move further with this support.
>
> Thanks !
> Eugen
>

Gentle ping


>>
>> Changes in v4:
>> - renamed i2c-ana-filter to i2c-analog-filter
>> - renamed i2c-dig-filter to i2c-digital-filter
>>
>> Changes in v3:
>> - made bindings global for i2c controllers and modified accordingly
>> - gave up PADFCDF bit because it's a lack in datasheet
>> - the computation on the width of the spike is based on periph clock
>> as it
>> is done for hold time.
>>
>> Changes in v2:
>> - added device tree bindings and support for enable-ana-filt and
>> enable-dig-filt
>> - added the new properties to the DT for
>> sama5d4_xplained/sama5d2_xplained
>>
>> Eugen Hristev (9):
>>    dt-bindings: i2c: at91: add new compatible
>>    dt-bindings: i2c: add bindings for i2c analog and digital filter
>>    i2c: add support for filters optional properties
>>    i2c: at91: add new platform support for sam9x60
>>    i2c: at91: add support for digital filtering
>>    i2c: at91: add support for advanced digital filtering
>>    i2c: at91: add support for analog filtering
>>    ARM: dts: at91: sama5d2_xplained: add analog and digital filter for
>>      i2c
>>    ARM: dts: at91: sama5d4_xplained: add digital filter for i2c
>>
>>   Documentation/devicetree/bindings/i2c/i2c-at91.txt |  3 +-
>>   Documentation/devicetree/bindings/i2c/i2c.txt      | 18 ++++++++
>>   arch/arm/boot/dts/at91-sama5d2_xplained.dts        |  6 +++
>>   arch/arm/boot/dts/at91-sama5d4_xplained.dts        |  1 +
>>   drivers/i2c/busses/i2c-at91-core.c                 | 38
>> +++++++++++++++++
>>   drivers/i2c/busses/i2c-at91-master.c               | 49
>> ++++++++++++++++++++--
>>   drivers/i2c/busses/i2c-at91.h                      | 13 ++++++
>>   drivers/i2c/i2c-core-base.c                        |  6 +++
>>   include/linux/i2c.h                                |  6 +++
>>   9 files changed, 136 insertions(+), 4 deletions(-)
>>

2019-10-21 14:08:43

by Wolfram Sang

[permalink] [raw]
Subject: Re: [PATCH v5 0/9] i2c: add support for filters

On Mon, Oct 07, 2019 at 07:53:21AM +0000, [email protected] wrote:
>
>
> On 11.09.2019 11:24, Eugen Hristev - M18282 wrote:
> > From: Eugen Hristev <[email protected]>
> >
> > Hello,
> >
> > This series adds support for analog and digital filters for i2c controllers
> >
> > This series is based on the series:
> > [PATCH v2 0/9] i2c: at91: filters support for at91 SoCs
> > and later
> > [PATCH v4 0/9] i2c: add support for filters
> > and enhanced to add the bindings for all controllers plus an extra bindings
> > for the width of the spikes in nanoseconds (digital filters) and cut-off
> > frequency (analog filters)
> >
> > First, bindings are created for
> > 'i2c-analog-filter'
> > 'i2c-digital-filter'
> > 'i2c-digital-filter-width-ns'
> > 'i2c-analog-filter-cutoff-frequency'
> >
> > The support is added in the i2c core to retrieve filter width/cutoff frequency
> > and add it to the timings structure.
> > Next, the at91 driver is enhanced for supporting digital filter, advanced
> > digital filter (with selectable spike width) and the analog filter.
> >
> > Finally the device tree for two boards are modified to make use of the
> > new properties.
> >
> > This series is the result of the comments on the ML in the direction
> > requested: to make the bindings globally available for i2c drivers.
> >
> > Changes in v5:
> > - renamed i2c-filter-width-ns to i2c-digital-filter-width-ns as this
> > is applicable only to digital filter
> > - created new binding i2c-digital-filter-width-ns for analog filters.
>
> Hello Wolfram and Peter,
>
> Are you happy with the changes in this version? I haven't heard from you
> since this latest update.
> I am interested to know if anymore changes are required or maybe we can
> move further with this support.

So, I had a look now and I am happy. I will give Peter one more day to
comment, otherwise I'll apply it tomorrow.

Thanks for your patience and keeping at it!


Attachments:
(No filename) (1.96 kB)
signature.asc (849.00 B)
Download all attachments

2019-10-21 15:24:12

by Peter Rosin

[permalink] [raw]
Subject: Re: [PATCH v5 3/9] i2c: add support for filters optional properties

On 2019-09-11 10:24, [email protected] wrote:
> From: Eugen Hristev <[email protected]>
>
> i2c-digital-filter-width-ns:
> This optional timing property specifies the width of the spikes on the i2c
> lines (in ns) that can be filtered out by built-in digital filters which are
> embedded in some i2c controllers.
> i2c-analog-filter-cutoff-frequency:
> This optional timing property specifies the cutoff frequency of a low-pass
> analog filter built-in i2c controllers. This low pass filter is used to filter
> out high frequency noise on the i2c lines. Specified in Hz.
> Include these properties in the timings structure and read them as integers.
>
> Signed-off-by: Eugen Hristev <[email protected]>
> ---
> drivers/i2c/i2c-core-base.c | 6 ++++++
> include/linux/i2c.h | 6 ++++++
> 2 files changed, 12 insertions(+)
>
> diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
> index 9c440fa..c9fcb16 100644
> --- a/drivers/i2c/i2c-core-base.c
> +++ b/drivers/i2c/i2c-core-base.c
> @@ -1658,6 +1658,12 @@ void i2c_parse_fw_timings(struct device *dev, struct i2c_timings *t, bool use_de
> t->sda_fall_ns = t->scl_fall_ns;
>
> device_property_read_u32(dev, "i2c-sda-hold-time-ns", &t->sda_hold_ns);
> +
> + device_property_read_u32(dev, "i2c-digital-filter-width-ns",
> + &t->digital_filter_width_ns);
> +
> + device_property_read_u32(dev, "i2c-analog-filter-cutoff-frequency",
> + &t->analog_filter_cutoff_freq_hz);
> }
> EXPORT_SYMBOL_GPL(i2c_parse_fw_timings);
>
> diff --git a/include/linux/i2c.h b/include/linux/i2c.h
> index fa5552c..26ce143 100644
> --- a/include/linux/i2c.h
> +++ b/include/linux/i2c.h
> @@ -575,6 +575,10 @@ struct i2c_lock_operations {
> * @scl_int_delay_ns: time IP core additionally needs to setup SCL in ns
> * @sda_fall_ns: time SDA signal takes to fall in ns; t(f) in the I2C specification
> * @sda_hold_ns: time IP core additionally needs to hold SDA in ns
> + * @digital_filter_width_ns: width in ns of spikes on i2c lines that the IP core
> + * digital filter can filter out
> + * @analog_filter_cutoff_freq_hz: threshold frequency for the low pass IP core
> + analog filter

The indentation is a little bit excessive and also off. Other comments in the
file just uses a single tab after the asterisk in this scenario. Also, the last
of the new lines is missing that leading asterisk.

Cheers,
Peter

> */
> struct i2c_timings {
> u32 bus_freq_hz;
> @@ -583,6 +587,8 @@ struct i2c_timings {
> u32 scl_int_delay_ns;
> u32 sda_fall_ns;
> u32 sda_hold_ns;
> + u32 digital_filter_width_ns;
> + u32 analog_filter_cutoff_freq_hz;
> };
>
> /**
>

2019-10-21 15:26:40

by Peter Rosin

[permalink] [raw]
Subject: Re: [PATCH v5 0/9] i2c: add support for filters

On 2019-10-21 16:05, Wolfram Sang wrote:
> On Mon, Oct 07, 2019 at 07:53:21AM +0000, [email protected] wrote:
>>
>>
>> On 11.09.2019 11:24, Eugen Hristev - M18282 wrote:
>>> From: Eugen Hristev <[email protected]>
>>>
>>> Hello,
>>>
>>> This series adds support for analog and digital filters for i2c controllers
>>>
>>> This series is based on the series:
>>> [PATCH v2 0/9] i2c: at91: filters support for at91 SoCs
>>> and later
>>> [PATCH v4 0/9] i2c: add support for filters
>>> and enhanced to add the bindings for all controllers plus an extra bindings
>>> for the width of the spikes in nanoseconds (digital filters) and cut-off
>>> frequency (analog filters)
>>>
>>> First, bindings are created for
>>> 'i2c-analog-filter'
>>> 'i2c-digital-filter'
>>> 'i2c-digital-filter-width-ns'
>>> 'i2c-analog-filter-cutoff-frequency'
>>>
>>> The support is added in the i2c core to retrieve filter width/cutoff frequency
>>> and add it to the timings structure.
>>> Next, the at91 driver is enhanced for supporting digital filter, advanced
>>> digital filter (with selectable spike width) and the analog filter.
>>>
>>> Finally the device tree for two boards are modified to make use of the
>>> new properties.
>>>
>>> This series is the result of the comments on the ML in the direction
>>> requested: to make the bindings globally available for i2c drivers.
>>>
>>> Changes in v5:
>>> - renamed i2c-filter-width-ns to i2c-digital-filter-width-ns as this
>>> is applicable only to digital filter
>>> - created new binding i2c-digital-filter-width-ns for analog filters.
>>
>> Hello Wolfram and Peter,
>>
>> Are you happy with the changes in this version? I haven't heard from you
>> since this latest update.
>> I am interested to know if anymore changes are required or maybe we can
>> move further with this support.
>
> So, I had a look now and I am happy. I will give Peter one more day to
> comment, otherwise I'll apply it tomorrow.

I had another read-through and only found one nit which is in a separate
message. You can add

Reviewed-by: Peter Rosin <[email protected]>

for the whole series.

Cheers,
Peter

> Thanks for your patience and keeping at it!
>

2019-10-23 11:05:25

by Eugen Hristev

[permalink] [raw]
Subject: Re: [PATCH v5 0/9] i2c: add support for filters



On 21.10.2019 18:23, Peter Rosin wrote:

>
> On 2019-10-21 16:05, Wolfram Sang wrote:
>> On Mon, Oct 07, 2019 at 07:53:21AM +0000, [email protected] wrote:
>>>
>>>
>>> On 11.09.2019 11:24, Eugen Hristev - M18282 wrote:
>>>> From: Eugen Hristev <[email protected]>
>>>>
>>>> Hello,
>>>>
>>>> This series adds support for analog and digital filters for i2c controllers
>>>>
>>>> This series is based on the series:
>>>> [PATCH v2 0/9] i2c: at91: filters support for at91 SoCs
>>>> and later
>>>> [PATCH v4 0/9] i2c: add support for filters
>>>> and enhanced to add the bindings for all controllers plus an extra bindings
>>>> for the width of the spikes in nanoseconds (digital filters) and cut-off
>>>> frequency (analog filters)
>>>>
>>>> First, bindings are created for
>>>> 'i2c-analog-filter'
>>>> 'i2c-digital-filter'
>>>> 'i2c-digital-filter-width-ns'
>>>> 'i2c-analog-filter-cutoff-frequency'
>>>>
>>>> The support is added in the i2c core to retrieve filter width/cutoff frequency
>>>> and add it to the timings structure.
>>>> Next, the at91 driver is enhanced for supporting digital filter, advanced
>>>> digital filter (with selectable spike width) and the analog filter.
>>>>
>>>> Finally the device tree for two boards are modified to make use of the
>>>> new properties.
>>>>
>>>> This series is the result of the comments on the ML in the direction
>>>> requested: to make the bindings globally available for i2c drivers.
>>>>
>>>> Changes in v5:
>>>> - renamed i2c-filter-width-ns to i2c-digital-filter-width-ns as this
>>>> is applicable only to digital filter
>>>> - created new binding i2c-digital-filter-width-ns for analog filters.
>>>
>>> Hello Wolfram and Peter,
>>>
>>> Are you happy with the changes in this version? I haven't heard from you
>>> since this latest update.
>>> I am interested to know if anymore changes are required or maybe we can
>>> move further with this support.
>>
>> So, I had a look now and I am happy. I will give Peter one more day to
>> comment, otherwise I'll apply it tomorrow.
>
> I had another read-through and only found one nit which is in a separate
> message. You can add
>
> Reviewed-by: Peter Rosin <[email protected]>
>
> for the whole series.

Hello Peter and Wolfram,

Thanks for reviewing.
Send another version of the patch with the nit ?
Or how would you like to proceed ?

Thanks,
Eugen

>
> Cheers,
> Peter
>
>> Thanks for your patience and keeping at it!
>>
>
>
>

2019-10-23 16:42:13

by Wolfram Sang

[permalink] [raw]
Subject: Re: [PATCH v5 0/9] i2c: add support for filters

> Send another version of the patch with the nit ?

That would be easiest for me.

Thanks!


Attachments:
(No filename) (98.00 B)
signature.asc (849.00 B)
Download all attachments

2019-10-25 18:51:32

by Wolfram Sang

[permalink] [raw]
Subject: Re: [PATCH v5 0/9] i2c: add support for filters

On Wed, Sep 11, 2019 at 08:24:14AM +0000, [email protected] wrote:
> From: Eugen Hristev <[email protected]>
>
> Hello,
>
> This series adds support for analog and digital filters for i2c controllers
>
> This series is based on the series:
> [PATCH v2 0/9] i2c: at91: filters support for at91 SoCs
> and later
> [PATCH v4 0/9] i2c: add support for filters
> and enhanced to add the bindings for all controllers plus an extra bindings
> for the width of the spikes in nanoseconds (digital filters) and cut-off
> frequency (analog filters)
>
> First, bindings are created for
> 'i2c-analog-filter'
> 'i2c-digital-filter'
> 'i2c-digital-filter-width-ns'
> 'i2c-analog-filter-cutoff-frequency'
>
> The support is added in the i2c core to retrieve filter width/cutoff frequency
> and add it to the timings structure.
> Next, the at91 driver is enhanced for supporting digital filter, advanced
> digital filter (with selectable spike width) and the analog filter.
>
> Finally the device tree for two boards are modified to make use of the
> new properties.
>
> This series is the result of the comments on the ML in the direction
> requested: to make the bindings globally available for i2c drivers.

Applied patches 1-7 to for-next (patch 3 is v6). Thanks for your
patience and thanks to Ludovic and Peter for the review! Patches 8-9
should go via the at91 tree.


Attachments:
(No filename) (1.39 kB)
signature.asc (849.00 B)
Download all attachments

2019-10-25 19:39:10

by Ludovic Desroches

[permalink] [raw]
Subject: Re: [PATCH v5 0/9] i2c: add support for filters

On Thu, Oct 24, 2019 at 08:30:35PM +0200, Wolfram Sang wrote:
> On Wed, Sep 11, 2019 at 08:24:14AM +0000, [email protected] wrote:
> > From: Eugen Hristev <[email protected]>
> >
> > Hello,
> >
> > This series adds support for analog and digital filters for i2c controllers
> >
> > This series is based on the series:
> > [PATCH v2 0/9] i2c: at91: filters support for at91 SoCs
> > and later
> > [PATCH v4 0/9] i2c: add support for filters
> > and enhanced to add the bindings for all controllers plus an extra bindings
> > for the width of the spikes in nanoseconds (digital filters) and cut-off
> > frequency (analog filters)
> >
> > First, bindings are created for
> > 'i2c-analog-filter'
> > 'i2c-digital-filter'
> > 'i2c-digital-filter-width-ns'
> > 'i2c-analog-filter-cutoff-frequency'
> >
> > The support is added in the i2c core to retrieve filter width/cutoff frequency
> > and add it to the timings structure.
> > Next, the at91 driver is enhanced for supporting digital filter, advanced
> > digital filter (with selectable spike width) and the analog filter.
> >
> > Finally the device tree for two boards are modified to make use of the
> > new properties.
> >
> > This series is the result of the comments on the ML in the direction
> > requested: to make the bindings globally available for i2c drivers.
>
> Applied patches 1-7 to for-next (patch 3 is v6). Thanks for your
> patience and thanks to Ludovic and Peter for the review! Patches 8-9
> should go via the at91 tree.
>

Thanks, patch 8 and 9 applied to at91-dt.

Regards

Ludovic