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Message-ID: <CAGdLNWEK4dtz7skTvQ8v=fhc=SS2V6tEa-e_bcLEaKkrXt08ew@mail.gmail.com>
Date: Thu, 11 Sep 2014 19:39:48 -0600
From: Azael Avalos <coproscefalo@...il.com>
To: Darren Hart <dvhart@...radead.org>
Cc: Matthew Garrett <matthew.garrett@...ula.com>,
"platform-driver-x86@...r.kernel.org"
<platform-driver-x86@...r.kernel.org>,
"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v2 4/5] toshiba_acpi: Support new keyboard backlight type
Hi Darren,
2014-09-11 18:36 GMT-06:00 Darren Hart <dvhart@...radead.org>:
> On Wed, Sep 10, 2014 at 09:01:56PM -0600, Azael Avalos wrote:
>
> Hi Azael,
>
>> Newer Toshiba models now come with a new (and different) keyboard
>> backlight implementation with three modes of operation: TIMER,
>> ON and OFF, and the LED is controlled internally by the firmware.
>>
>> This patch adds support for that type of backlight, changing the
>> existing code to accomodate the new implementation.
>>
>> The timeout value range is now 1-60 seconds, and the accepted
>> modes are now: 1 (FN-Z), 2 (AUTO or TIMER), 8(ON) and 10 (OFF),
>> this adds two new entries keyboard_type and available_kbd_modes,
>> the first shows the keyboard type and the latter shows the
>> supported modes depending on the type.
>>
>> Signed-off-by: Azael Avalos <coproscefalo@...il.com>
>> ---
>> drivers/platform/x86/toshiba_acpi.c | 117 +++++++++++++++++++++++++++++++-----
>> 1 file changed, 102 insertions(+), 15 deletions(-)
>>
>> diff --git a/drivers/platform/x86/toshiba_acpi.c b/drivers/platform/x86/toshiba_acpi.c
>> index 4c8fa7b..08147c5 100644
>> --- a/drivers/platform/x86/toshiba_acpi.c
>> +++ b/drivers/platform/x86/toshiba_acpi.c
>> @@ -140,6 +140,10 @@ MODULE_LICENSE("GPL");
>> #define HCI_WIRELESS_BT_POWER 0x80
>> #define SCI_KBD_MODE_FNZ 0x1
>> #define SCI_KBD_MODE_AUTO 0x2
>> +#define SCI_KBD_MODE_ON 0x8
>> +#define SCI_KBD_MODE_OFF 0x10
>> +#define SCI_KBD_MODE_MAX SCI_KBD_MODE_OFF
>> +#define SCI_KBD_TIME_MAX 0x3c001a
>>
>> struct toshiba_acpi_dev {
>> struct acpi_device *acpi_dev;
>> @@ -155,6 +159,7 @@ struct toshiba_acpi_dev {
>> int force_fan;
>> int last_key_event;
>> int key_event_valid;
>> + int kbd_type;
>> int kbd_mode;
>> int kbd_time;
>>
>> @@ -495,6 +500,42 @@ static enum led_brightness toshiba_illumination_get(struct led_classdev *cdev)
>> }
>>
>> /* KBD Illumination */
>> +static int toshiba_kbd_illum_available(struct toshiba_acpi_dev *dev)
>> +{
>> + u32 in[HCI_WORDS] = { SCI_GET, SCI_KBD_ILLUM_STATUS, 0, 0, 0, 0 };
>> + u32 out[HCI_WORDS];
>> + acpi_status status;
>> +
>> + if (!sci_open(dev))
>> + return 0;
>> +
>> + status = hci_raw(dev, in, out);
>> + sci_close(dev);
>> + if (ACPI_FAILURE(status) || out[0] == SCI_INPUT_DATA_ERROR) {
>> + pr_err("ACPI call to query kbd illumination support failed\n");
>> + return 0;
>> + } else if (out[0] == HCI_NOT_SUPPORTED) {
>> + pr_info("Keyboard illumination not available\n");
>> + return 0;
>> + }
>> +
>> + /* Check for keyboard backlight timeout max value,
>> + /* previous kbd backlight implementation set this to
>
> Extra / ^
>
>> + * 0x3c0003, and now the new implementation set this
>> + * to 0x3c001a, use this to distinguish between them
>> + */
>> + if (out[3] == SCI_KBD_TIME_MAX)
>> + dev->kbd_type = 2;
>> + else
>> + dev->kbd_type = 1;
>> + /* Get the current keyboard backlight mode */
>> + dev->kbd_mode = out[2] & SCI_KBD_MODE_MASK;
>> + /* Get the current time (1-60 seconds) */
>> + dev->kbd_time = out[2] >> HCI_MISC_SHIFT;
>> +
>> + return 1;
>> +}
>> +
>> static int toshiba_kbd_illum_status_set(struct toshiba_acpi_dev *dev, u32 time)
>> {
>> u32 result;
>> @@ -1268,20 +1309,46 @@ static ssize_t toshiba_kbd_bl_mode_store(struct device *dev,
>> ret = kstrtoint(buf, 0, &mode);
>> if (ret)
>> return ret;
>> - if (mode != SCI_KBD_MODE_FNZ && mode != SCI_KBD_MODE_AUTO)
>> + if (mode != SCI_KBD_MODE_FNZ && mode != SCI_KBD_MODE_AUTO &&
>> + mode != SCI_KBD_MODE_ON && mode != SCI_KBD_MODE_OFF)
>> return -EINVAL;
>
> Since you have to check for a type::mode match anyway, this initial test is
> redundant. I suggest inverting the type::mode match below and make it
> exhaustive, something like:
>
>>
>> + /* Check for supported modes depending on keyboard backlight type */
>> + if (toshiba->kbd_type == 1) {
>> + /* Type 1 supports SCI_KBD_MODE_FNZ and SCI_KBD_MODE_AUTO */
>> + if (mode == SCI_KBD_MODE_ON || mode == SCI_KBD_MODE_OFF)
>
>
> if (mode != SCI_KBD_MODE_FNZ && mode != SCI_KBD_MODE_AUTO)
>
>
> The net number of tests is ultimately smaller and it's fewer lines of code.
Ok
>
>> + return -EINVAL;
>> + } else if (toshiba->kbd_type == 2) {
>> + /* Type 2 doesn't support SCI_KBD_MODE_FNZ */
>> + if (mode == SCI_KBD_MODE_FNZ)
>> + return -EINVAL;
>> + }
>> +
>> /* Set the Keyboard Backlight Mode where:
>> - * Mode - Auto (2) | FN-Z (1)
>> * Auto - KBD backlight turns off automatically in given time
>> * FN-Z - KBD backlight "toggles" when hotkey pressed
>> + * ON - KBD backlight is always on
>> + * OFF - KBD backlight is always off
>> */
>> +
>> + /* Only make a change if the actual mode has changed */
>> if (toshiba->kbd_mode != mode) {
>> + /* Shift the time to "base time" (0x3c0000 == 60 seconds) */
>> time = toshiba->kbd_time << HCI_MISC_SHIFT;
>> - time = time + toshiba->kbd_mode;
>> +
>> + /* OR the "base time" to the actual method format */
>> + if (toshiba->kbd_type == 1) {
>> + /* Type 1 requires the current mode */
>> + time |= toshiba->kbd_mode;
>> + } else if (toshiba->kbd_type == 2) {
>> + /* Type 2 requires the desired mode */
>> + time |= mode;
>> + }
>> +
>> ret = toshiba_kbd_illum_status_set(toshiba, time);
>> if (ret)
>> return ret;
>> +
>> toshiba->kbd_mode = mode;
>> }
>>
>> @@ -1293,12 +1360,31 @@ static ssize_t toshiba_kbd_bl_mode_show(struct device *dev,
>> char *buf)
>> {
>> struct toshiba_acpi_dev *toshiba = dev_get_drvdata(dev);
>> - u32 time;
>>
>> - if (toshiba_kbd_illum_status_get(toshiba, &time) < 0)
>> - return -EIO;
>> + return sprintf(buf, "%x\n", toshiba->kbd_mode);
>
>
> I understand this isn't new, and I don't see an obvious path to failure - have
> you verified dev_get_drvdata CANNOT return NULL or a bad pointer ever?
>
Well, since we are using dev_set_drvdata on startup (toshiba_acpi_add),
it should never return a bad pointer, however, lets play on the safe side
and I'll add a check for NULL because that's what dev_get_drvdata
returns in case of a non valid pointer
>
>
>> +}
>>
>> - return sprintf(buf, "%i\n", time & 0x07);
>> +static ssize_t toshiba_kbd_type_show(struct device *dev,
>> + struct device_attribute *attr,
>> + char *buf)
>> +{
>> + struct toshiba_acpi_dev *toshiba = dev_get_drvdata(dev);
>> +
>> + return sprintf(buf, "%d\n", toshiba->kbd_type);
>> +}
>> +
>> +static ssize_t toshiba_available_kbd_modes_show(struct device *dev,
>> + struct device_attribute *attr,
>> + char *buf)
>> +{
>> + struct toshiba_acpi_dev *toshiba = dev_get_drvdata(dev);
>> +
>> + if (toshiba->kbd_type == 1)
>> + return sprintf(buf, "%x %x\n",
>> + SCI_KBD_MODE_FNZ, SCI_KBD_MODE_AUTO);
>> +
>> + return sprintf(buf, "%x %x %x\n",
>> + SCI_KBD_MODE_AUTO, SCI_KBD_MODE_ON, SCI_KBD_MODE_OFF);
>> }
>>
>> static ssize_t toshiba_kbd_bl_timeout_store(struct device *dev,
>> @@ -1390,6 +1476,9 @@ static ssize_t toshiba_position_show(struct device *dev,
>>
>> static DEVICE_ATTR(kbd_backlight_mode, S_IRUGO | S_IWUSR,
>> toshiba_kbd_bl_mode_show, toshiba_kbd_bl_mode_store);
>> +static DEVICE_ATTR(keyboard_type, S_IRUGO, toshiba_kbd_type_show, NULL);
>> +static DEVICE_ATTR(available_kbd_modes, S_IRUGO,
>> + toshiba_available_kbd_modes_show, NULL);
>
>
> Please keep the naming as consistent as possible. We're using "kbd" here instead
> of "keyboard" here for most everything else.
Ok
>
> A user may not key-in that kbd_backlight_mode is the setting and the options are
> available_kbd_modes, since kbd_backlight_mode could conceivably be different
> from kbd_modes. Let's make it very easy for someone trying to discover this
> interface by using consistent terminology throughout.
>
>
>> static DEVICE_ATTR(kbd_backlight_timeout, S_IRUGO | S_IWUSR,
>> toshiba_kbd_bl_timeout_show, toshiba_kbd_bl_timeout_store);
>> static DEVICE_ATTR(touchpad, S_IRUGO | S_IWUSR,
>> @@ -1398,6 +1487,8 @@ static DEVICE_ATTR(position, S_IRUGO, toshiba_position_show, NULL);
>>
>> static struct attribute *toshiba_attributes[] = {
>> &dev_attr_kbd_backlight_mode.attr,
>> + &dev_attr_keyboard_type.attr,
>> + &dev_attr_available_kbd_modes.attr,
>> &dev_attr_kbd_backlight_timeout.attr,
>> &dev_attr_touchpad.attr,
>> &dev_attr_position.attr,
>> @@ -1414,7 +1505,7 @@ static umode_t toshiba_sysfs_is_visible(struct kobject *kobj,
>> if (attr == &dev_attr_kbd_backlight_mode.attr)
>> exists = (drv->kbd_illum_supported) ? true : false;
>> else if (attr == &dev_attr_kbd_backlight_timeout.attr)
>> - exists = (drv->kbd_mode == SCI_KBD_MODE_AUTO) ? true : false;
>> + exists = (drv->kbd_mode == SCI_KBD_MODE_FNZ) ? false : true;
>
> Is this correct? This would mean a timeout is available even if mode is OFF?
Right now yes, as I wasn't sure if I could create/delete files from sysfs, so
perhaps whenever the user is not on AUTO call sysfs_update_group and leave
toshiba_sysfs_is_visible as it was.
>
>
>> else if (attr == &dev_attr_touchpad.attr)
>> exists = (drv->touchpad_supported) ? true : false;
>> else if (attr == &dev_attr_position.attr)
>> @@ -1759,15 +1850,11 @@ static int toshiba_acpi_add(struct acpi_device *acpi_dev)
>> dev->eco_supported = 1;
>> }
>>
>> - ret = toshiba_kbd_illum_status_get(dev, &dummy);
>> - if (!ret) {
>> - dev->kbd_time = dummy >> HCI_MISC_SHIFT;
>> - dev->kbd_mode = dummy & 0x07;
>> - }
>> - dev->kbd_illum_supported = !ret;
>> + dev->kbd_illum_supported = toshiba_kbd_illum_available(dev);
>> /*
>> * Only register the LED if KBD illumination is supported
>> - * and the keyboard backlight operation mode is set to FN-Z
>> + * and the keyboard backlight operation mode is set to FN-Z,
>> + * keyboard backlight type 2 returns 0x8400 (HCI WRITE PROTECTED)
>
> Hrm, I'm not following how this relates to the code block that follows...
I just wanted to place a note for others reading the code, the kbd led
method is always available, so if someone else tries to expose the
kbd led to userspace on kbd bl type 2, it will return a write protected
error on writing (reading is always accessible).
>
> Thanks Azael,
>
> --
> Darren Hart
> Intel Open Source Technology Center
I'll re-send an updated patch with the observations mentioned here,
and also adding an extra line of code that went missing.
Cheers
Azael
--
-- El mundo apesta y vosotros apestais tambien --
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