Re: [PATCH v6 4/4] Input: Add TouchNetix aXiom I2C Touchscreen support

[Marco Felsch]

Hi Andrew,

thanks for your feedback! Please see below.

On 26-03-13, Andrew Thomas wrote:
> On Tue, Mar 03, 2026 at 11:41:22PM +0100, Marco Felsch wrote:
> >This adds the initial support for the TouchNetix AX54A touchcontroller
> >which is part of TouchNetix's aXiom touchscreen controller family.
> >
> >The TouchNetix aXiom family provides two physical interfaces: SPI and
> >I2C. This patch covers only the I2C interface.
> >
> >Apart the input event handling the driver supports firmware updates too.
> >One firmware interface handles the touchcontroller firmware (AXFW)
> >update the other handles the touchcontroller configuration (TH2CFGBIN)
> >update.
> >
> >Signed-off-by: Marco Felsch <m.felsch@xxxxxxxxxxxxxx>
> >---

...

> >+static int axiom_u02_enter_bootloader(struct axiom_data *ts)
> >+{
> >+	struct axiom_u02_rev1_system_manager_msg msg = { };
> >+	struct device *dev = ts->dev;
> >+	unsigned int val;
> >+	int error;
> >+
> >+	if (!axiom_driver_supports_usage(ts, AXIOM_U02))
> >+		return -EINVAL;
> >+
> >+	/*
> >+	 * Enter the bootloader mode requires 3 consecutive messages so we can't
> >+	 * check for the response.
> >+	 * TODO: Check if it's required to add a delay between the consecutive
> >+	 * CMD_ENTERBOOTLOADER cmds.
> >+	 */
> >+	msg.command = cpu_to_le16(AXIOM_U02_REV1_CMD_ENTERBOOTLOADER);
> >+	msg.parameters[0] = cpu_to_le16(AXIOM_U02_REV1_PARAM0_ENTERBOOLOADER_KEY1);
> >+	error = axiom_u02_send_msg(ts, &msg, false);
> 
> As mentioned before the delay between commands is too short and the
> next command is sent before u02 is ready, which means the driver fails
> to put axiom into the bootloader.

Please see my comment [1].

> Have you tested with an i2c speed of 400KHz?

Yes, my target platform is based on a i.MX8MP.

> All you need is to put true in above to wait for the bootloader command.
> error = axiom_u02_send_msg(ts, &msg, true);

Please see my comment [1].

> Just dont do it for the last command.

Please see my comment [1].

> I am not too sure why you are having issues with this, this is how we
> do it for all our devices.

Please see my comment [1].

On what platform do you perform the tests?

> >+	if (error) {
> >+		dev_err(dev, "Failed to send bootloader-key1: %d\n", error);
> >+		return error;
> >+	}
> >+
> >+	msg.parameters[0] = cpu_to_le16(AXIOM_U02_REV1_PARAM0_ENTERBOOLOADER_KEY2);
> >+	error = axiom_u02_send_msg(ts, &msg, false);
> 
> Here also.

Please see my comment [1].

> >+	if (error) {
> >+		dev_err(dev, "Failed to send bootloader-key2: %d\n", error);
> >+		return error;
> >+	}
> >+
> >+	msg.parameters[0] = cpu_to_le16(AXIOM_U02_REV1_PARAM0_ENTERBOOLOADER_KEY3);
> >+	error = axiom_u02_send_msg(ts, &msg, false);
> >+	if (error) {
> >+		dev_err(dev, "Failed to send bootloader-key3: %d\n", error);
> >+		return error;
> >+	}
> >+
> >+	/* Sleep before the first read to give the device time */
> >+	fsleep(250 * USEC_PER_MSEC);
> >+
> >+	/* Wait till the device reports it is in bootloader mode */
> >+	error = regmap_read_poll_timeout(ts->regmap,
> >+					 AXIOM_U31_REV1_DEVICE_ID_HIGH_REG, val,
> >+					 FIELD_GET(AXIOM_U31_REV1_MODE_MASK, val) ==
> >+						AXIOM_U31_REV1_MODE_BLP,
> >+					 250 * USEC_PER_MSEC, USEC_PER_SEC);
> >+	if (error)
> >+		return error;
> >+
> >+	return 0;
> >+}
> >+
> 
> ...
> 
> 
> Other than the above comments I have no issues with the driver.

If you're fine with the patch you could add your acked-by [2] :)

> We can support more usages in a later patch.

Sure :)

[1] https://lore.kernel.org/all/4x3dnedfzf3rqzsy3wjdoj6yaxmy6kop37xhxeao4vjer7ifdi@35ux42ztq3eb/
[2] https://docs.kernel.org/process/submitting-patches.html#when-to-use-acked-by-cc-and-co-developed-by

Regards,
  Marco
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