2021-03-16 02:31:42

by Andreas Kemnade

Subject: [PATCH v4] mfd: ntxec: Support for EC in Tolino Shine 2 HD

Add the version of the EC in the Tolino Shine 2 HD
to the supported versions. It seems not to have an RTC
and does not ack data written to it.
The vendor kernel happily ignores write errors, using
I2C via userspace i2c-set also shows the error.
So add a quirk to ignore that error.

PWM can be successfully configured despite of that error.

Signed-off-by: Andreas Kemnade <[email protected]>
Reviewed-by: Jonathan Neuschäfer <[email protected]>
---
Changes in v4:
- rename subdevices back to v2 (suggested by Jonathan)
- initialize subdevs in switch

Changes in v3:
- remove have_rtc variable
- rename subdevices again

Changes in v2:
- more comments about stacking regmap construction
- fix accidential line removal
- better naming for subdevices

drivers/mfd/ntxec.c | 56 ++++++++++++++++++++++++++++++++++++---
include/linux/mfd/ntxec.h | 1 +
2 files changed, 54 insertions(+), 3 deletions(-)

diff --git a/drivers/mfd/ntxec.c b/drivers/mfd/ntxec.c
index 957de2b03529..b711e73eedcb 100644
--- a/drivers/mfd/ntxec.c
+++ b/drivers/mfd/ntxec.c
@@ -96,6 +96,38 @@ static struct notifier_block ntxec_restart_handler = {
.priority = 128,
};

+static int regmap_ignore_write(void *context,
+ unsigned int reg, unsigned int val)
+
+{
+ struct regmap *regmap = context;
+
+ regmap_write(regmap, reg, val);
+
+ return 0;
+}
+
+static int regmap_wrap_read(void *context, unsigned int reg,
+ unsigned int *val)
+{
+ struct regmap *regmap = context;
+
+ return regmap_read(regmap, reg, val);
+}
+
+/*
+ * Some firmware versions do not ack written data, add a wrapper. It
+ * is used to stack another regmap on top.
+ */
+static const struct regmap_config regmap_config_noack = {
+ .name = "ntxec_noack",
+ .reg_bits = 8,
+ .val_bits = 16,
+ .cache_type = REGCACHE_NONE,
+ .reg_write = regmap_ignore_write,
+ .reg_read = regmap_wrap_read
+};
+
static const struct regmap_config regmap_config = {
.name = "ntxec",
.reg_bits = 8,
@@ -104,16 +136,22 @@ static const struct regmap_config regmap_config = {
.val_format_endian = REGMAP_ENDIAN_BIG,
};

-static const struct mfd_cell ntxec_subdevices[] = {
+static const struct mfd_cell ntxec_subdev[] = {
{ .name = "ntxec-rtc" },
{ .name = "ntxec-pwm" },
};

+static const struct mfd_cell ntxec_subdev_pwm[] = {
+ { .name = "ntxec-pwm" },
+};
+
static int ntxec_probe(struct i2c_client *client)
{
struct ntxec *ec;
unsigned int version;
int res;
+ const struct mfd_cell *subdevs;
+ size_t n_subdevs;

ec = devm_kmalloc(&client->dev, sizeof(*ec), GFP_KERNEL);
if (!ec)
@@ -137,6 +175,18 @@ static int ntxec_probe(struct i2c_client *client)
/* Bail out if we encounter an unknown firmware version */
switch (version) {
case NTXEC_VERSION_KOBO_AURA:
+ subdevs = ntxec_subdev;
+ n_subdevs = ARRAY_SIZE(ntxec_subdev);
+ break;
+ case NTXEC_VERSION_TOLINO_SHINE2:
+ subdevs = ntxec_subdev_pwm;
+ n_subdevs = ARRAY_SIZE(ntxec_subdev_pwm);
+ /* Another regmap stacked on top of the other */
+ ec->regmap = devm_regmap_init(ec->dev, NULL,
+ ec->regmap,
+ &regmap_config_noack);
+ if (IS_ERR(ec->regmap))
+ return PTR_ERR(ec->regmap);
break;
default:
dev_err(ec->dev,
@@ -181,8 +231,8 @@ static int ntxec_probe(struct i2c_client *client)

i2c_set_clientdata(client, ec);

- res = devm_mfd_add_devices(ec->dev, PLATFORM_DEVID_NONE, ntxec_subdevices,
- ARRAY_SIZE(ntxec_subdevices), NULL, 0, NULL);
+ res = devm_mfd_add_devices(ec->dev, PLATFORM_DEVID_NONE,
+ subdevs, n_subdevs, NULL, 0, NULL);
if (res)
dev_err(ec->dev, "Failed to add subdevices: %d\n", res);

diff --git a/include/linux/mfd/ntxec.h b/include/linux/mfd/ntxec.h
index 361204d125f1..26ab3b8eb612 100644
--- a/include/linux/mfd/ntxec.h
+++ b/include/linux/mfd/ntxec.h
@@ -33,5 +33,6 @@ static inline __be16 ntxec_reg8(u8 value)

/* Known firmware versions */
#define NTXEC_VERSION_KOBO_AURA 0xd726 /* found in Kobo Aura */
+#define NTXEC_VERSION_TOLINO_SHINE2 0xf110 /* found in Tolino Shine 2 HD */

#endif
--
2.29.2

2021-03-25 02:50:59

by Lee Jones

Subject: Re: [PATCH v4] mfd: ntxec: Support for EC in Tolino Shine 2 HD

On Mon, 15 Mar 2021, Andreas Kemnade wrote:

> Add the version of the EC in the Tolino Shine 2 HD
> to the supported versions. It seems not to have an RTC
> and does not ack data written to it.
> The vendor kernel happily ignores write errors, using
> I2C via userspace i2c-set also shows the error.
> So add a quirk to ignore that error.
>
> PWM can be successfully configured despite of that error.
>
> Signed-off-by: Andreas Kemnade <[email protected]>
> Reviewed-by: Jonathan Neuschäfer <[email protected]>
> ---
> Changes in v4:
> - rename subdevices back to v2 (suggested by Jonathan)
> - initialize subdevs in switch
>
> Changes in v3:
> - remove have_rtc variable
> - rename subdevices again
>
> Changes in v2:
> - more comments about stacking regmap construction
> - fix accidential line removal
> - better naming for subdevices
>
> drivers/mfd/ntxec.c | 56 ++++++++++++++++++++++++++++++++++++---
> include/linux/mfd/ntxec.h | 1 +
> 2 files changed, 54 insertions(+), 3 deletions(-)

Applied, thanks.

--
Lee Jones [李琼斯]
Senior Technical Lead - Developer Services
Linaro.org │ Open source software for Arm SoCs
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