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Message-ID: <559F14B8.6010705@synaptics.com>
Date: Thu, 9 Jul 2015 17:41:28 -0700
From: Andrew Duggan <aduggan@...aptics.com>
To: Gabriele Mazzotta <gabriele.mzt@...il.com>
CC: <linux-input@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
Jiri Kosina <jkosina@...e.cz>,
Benjamin Tissoires <benjamin.tissoires@...hat.com>
Subject: Re: [PATCH] HID: rmi: Write updated F11 control registers after reset
On 07/09/2015 03:40 PM, Gabriele Mazzotta wrote:
> On Thursday 09 July 2015 15:14:17 Andrew Duggan wrote:
>> When a device is reset the values of control registers will be reset to
>> the defaults. This patch reapplies the control register values set for F11
>> by the driver.
> Hi,
>
> thanks for this, it works as intended. I just added a couple of
> comments here below, but other than that
>
> Tested-by: Gabriele Mazzotta <gabriele.mzt@...il.com>
Thanks for testing!
>> Signed-off-by: Andrew Duggan <aduggan@...aptics.com>
>> ---
>> drivers/hid/hid-rmi.c | 41 ++++++++++++++++++++++++++++++++++-------
>> 1 file changed, 34 insertions(+), 7 deletions(-)
>>
>> diff --git a/drivers/hid/hid-rmi.c b/drivers/hid/hid-rmi.c
>> index af191a2..80c068f 100644
>> --- a/drivers/hid/hid-rmi.c
>> +++ b/drivers/hid/hid-rmi.c
>> @@ -40,6 +40,8 @@
>> #define RMI_DEVICE BIT(0)
>> #define RMI_DEVICE_HAS_PHYS_BUTTONS BIT(1)
>>
>> +#define RMI_F11_CTRL_REG_COUNT 12
>> +
>> enum rmi_mode_type {
>> RMI_MODE_OFF = 0,
>> RMI_MODE_ATTN_REPORTS = 1,
>> @@ -116,6 +118,8 @@ struct rmi_data {
>> unsigned int max_y;
>> unsigned int x_size_mm;
>> unsigned int y_size_mm;
>> + bool read_f11_ctrl_regs;
>> + u8 f11_ctrl_regs[RMI_F11_CTRL_REG_COUNT];
>>
>> unsigned int gpio_led_count;
>> unsigned int button_count;
>> @@ -557,6 +561,15 @@ static int rmi_set_sleep_mode(struct hid_device *hdev, int sleep_mode)
>>
>> static int rmi_suspend(struct hid_device *hdev, pm_message_t message)
>> {
>> + struct rmi_data *data = hid_get_drvdata(hdev);
>> + int ret;
>> +
>> + ret = rmi_read_block(hdev, data->f11.control_base_addr,
>> + data->f11_ctrl_regs, RMI_F11_CTRL_REG_COUNT);
>> + if (ret)
>> + hid_warn(hdev, "can not read F11 control registers\n");
> It seems that rmi_read_block() can fail because of timeouts after it
> has started filling the buffer, so isn't it better to set
> read_f11_ctrl_regs to false when it happens?
>
Another option would be to create a local buffer for the read and only
copy it to data->f11_ctrl_regs if we get all of the bytes. That way we
can ensure that rmi_post_reset will have a valid set of registers to
restore. Or we could also just remove the read from the suspend callback
altogether and just write the values we set in rmi_populate_f11 and not
worry about changes made outside the driver.
>> +
>> +
>> if (!device_may_wakeup(hdev->dev.parent))
>> return rmi_set_sleep_mode(hdev, RMI_SLEEP_DEEP_SLEEP);
>>
>> @@ -565,6 +578,7 @@ static int rmi_suspend(struct hid_device *hdev, pm_message_t message)
>>
>> static int rmi_post_reset(struct hid_device *hdev)
>> {
>> + struct rmi_data *data = hid_get_drvdata(hdev);
>> int ret;
>>
>> ret = rmi_set_mode(hdev, RMI_MODE_ATTN_REPORTS);
>> @@ -573,6 +587,14 @@ static int rmi_post_reset(struct hid_device *hdev)
>> return ret;
>> }
>>
>> + if (data->read_f11_ctrl_regs) {
>> + ret = rmi_write_block(hdev, data->f11.control_base_addr,
>> + data->f11_ctrl_regs, RMI_F11_CTRL_REG_COUNT);
>> + if (ret)
>> + hid_warn(hdev,
>> + "can not write F11 control registers after reset\n");
>> + }
>> +
>> if (!device_may_wakeup(hdev->dev.parent)) {
>> ret = rmi_set_sleep_mode(hdev, RMI_SLEEP_NORMAL);
>> if (ret) {
>> @@ -963,18 +985,23 @@ static int rmi_populate_f11(struct hid_device *hdev)
>> * and there is no way to know if the first 20 bytes are here or not.
>> * We use only the first 12 bytes, so get only them.
>> */
> Just a suggestion here. What about moving this comment right above the
> definition of RMI_F11_CTRL_REG_COUNT?
That makes sense. I can make this change in my v2.
>> - ret = rmi_read_block(hdev, data->f11.control_base_addr, buf, 12);
>> + ret = rmi_read_block(hdev, data->f11.control_base_addr,
>> + data->f11_ctrl_regs, RMI_F11_CTRL_REG_COUNT);
>> if (ret) {
>> hid_err(hdev, "can not read ctrl block of size 11: %d.\n", ret);
>> return ret;
>> }
>>
>> - data->max_x = buf[6] | (buf[7] << 8);
>> - data->max_y = buf[8] | (buf[9] << 8);
>> + /* data->f11_ctrl_regs now contains valid register data */
>> + data->read_f11_ctrl_regs = true;
>> +
>> + data->max_x = data->f11_ctrl_regs[6] | (data->f11_ctrl_regs[7] << 8);
>> + data->max_y = data->f11_ctrl_regs[8] | (data->f11_ctrl_regs[9] << 8);
>>
>> if (has_dribble) {
>> - buf[0] = buf[0] & ~BIT(6);
>> - ret = rmi_write(hdev, data->f11.control_base_addr, buf);
>> + data->f11_ctrl_regs[0] = data->f11_ctrl_regs[0] & ~BIT(6);
>> + ret = rmi_write(hdev, data->f11.control_base_addr,
>> + data->f11_ctrl_regs);
>> if (ret) {
>> hid_err(hdev, "can not write to control reg 0: %d.\n",
>> ret);
>> @@ -983,9 +1010,9 @@ static int rmi_populate_f11(struct hid_device *hdev)
>> }
>>
>> if (has_palm_detect) {
>> - buf[11] = buf[11] & ~BIT(0);
>> + data->f11_ctrl_regs[11] = data->f11_ctrl_regs[11] & ~BIT(0);
>> ret = rmi_write(hdev, data->f11.control_base_addr + 11,
>> - &buf[11]);
>> + &data->f11_ctrl_regs[11]);
>> if (ret) {
>> hid_err(hdev, "can not write to control reg 11: %d.\n",
>> ret);
>>
Andrew
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