diff mbox

[v2,3/3] acpi: lpss: call pwm_add_table() for bsw PWM device

Message ID 20170122161409.21601-4-hdegoede@redhat.com (mailing list archive)
State New, archived
Headers show

Commit Message

Hans de Goede Jan. 22, 2017, 4:14 p.m. UTC
On x86 we do not have devicetree to link the PWM controller and
the display controller together. So someone needs to call
pwm_add_table() to create the link, so that the i915 driver's
pwm_get(dev, "pwm_backlight") call returns the lpss' pwm0.

The PWM subsystem does not want to have pwm_add_table() calls
directly in PWM drivers (this leads to probe ordering issues),
so lets do it here since the acpi-lpss code is always builtin.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Thierry Reding <thierry.reding@gmail.com>
---
Changes in v2:
-Set new pwm_lookup module_name field in the table
---
 drivers/acpi/acpi_lpss.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

Comments

Thierry Reding Jan. 30, 2017, 8:18 a.m. UTC | #1
On Sun, Jan 22, 2017 at 05:14:09PM +0100, Hans de Goede wrote:
> On x86 we do not have devicetree to link the PWM controller and
> the display controller together. So someone needs to call
> pwm_add_table() to create the link, so that the i915 driver's
> pwm_get(dev, "pwm_backlight") call returns the lpss' pwm0.
> 
> The PWM subsystem does not want to have pwm_add_table() calls
> directly in PWM drivers (this leads to probe ordering issues),
> so lets do it here since the acpi-lpss code is always builtin.
> 
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> Acked-by: Thierry Reding <thierry.reding@gmail.com>
> ---
> Changes in v2:
> -Set new pwm_lookup module_name field in the table
> ---
>  drivers/acpi/acpi_lpss.c | 13 +++++++++++++
>  1 file changed, 13 insertions(+)

Rafael, do you mind if I take this through the PWM tree to resolve the
build-time dependency?

Thanks,
Thierry

> 
> diff --git a/drivers/acpi/acpi_lpss.c b/drivers/acpi/acpi_lpss.c
> index 8ea836c..794be64 100644
> --- a/drivers/acpi/acpi_lpss.c
> +++ b/drivers/acpi/acpi_lpss.c
> @@ -20,6 +20,7 @@
>  #include <linux/platform_data/clk-lpss.h>
>  #include <linux/pm_domain.h>
>  #include <linux/pm_runtime.h>
> +#include <linux/pwm.h>
>  #include <linux/delay.h>
>  
>  #include "internal.h"
> @@ -154,6 +155,17 @@ static void byt_i2c_setup(struct lpss_private_data *pdata)
>  	writel(0, pdata->mmio_base + LPSS_I2C_ENABLE);
>  }
>  
> +/* BSW PWM used for backlight control by the i915 driver */
> +static struct pwm_lookup bsw_pwm_lookup[] = {
> +	PWM_LOOKUP_MODNAME("80862288:00", 0, "0000:00:02.0", "pwm_backlight",
> +			   0, PWM_POLARITY_NORMAL, "pwm-lpss-platform"),
> +};
> +
> +static void bsw_pwm_setup(struct lpss_private_data *pdata)
> +{
> +	pwm_add_table(bsw_pwm_lookup, ARRAY_SIZE(bsw_pwm_lookup));
> +}
> +
>  static const struct lpss_device_desc lpt_dev_desc = {
>  	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR,
>  	.prv_offset = 0x800,
> @@ -191,6 +203,7 @@ static const struct lpss_device_desc byt_pwm_dev_desc = {
>  
>  static const struct lpss_device_desc bsw_pwm_dev_desc = {
>  	.flags = LPSS_SAVE_CTX | LPSS_NO_D3_DELAY,
> +	.setup = bsw_pwm_setup,
>  };
>  
>  static const struct lpss_device_desc byt_uart_dev_desc = {
> -- 
> 2.9.3
>
Rafael J. Wysocki Jan. 30, 2017, 8:28 a.m. UTC | #2
On Mon, Jan 30, 2017 at 9:18 AM, Thierry Reding
<thierry.reding@gmail.com> wrote:
> On Sun, Jan 22, 2017 at 05:14:09PM +0100, Hans de Goede wrote:
>> On x86 we do not have devicetree to link the PWM controller and
>> the display controller together. So someone needs to call
>> pwm_add_table() to create the link, so that the i915 driver's
>> pwm_get(dev, "pwm_backlight") call returns the lpss' pwm0.
>>
>> The PWM subsystem does not want to have pwm_add_table() calls
>> directly in PWM drivers (this leads to probe ordering issues),
>> so lets do it here since the acpi-lpss code is always builtin.
>>
>> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
>> Acked-by: Thierry Reding <thierry.reding@gmail.com>
>> ---
>> Changes in v2:
>> -Set new pwm_lookup module_name field in the table
>> ---
>>  drivers/acpi/acpi_lpss.c | 13 +++++++++++++
>>  1 file changed, 13 insertions(+)
>
> Rafael, do you mind if I take this through the PWM tree to resolve the
> build-time dependency?

No, I don't, please go ahead, unless Mika/Andy see any problems in it.

Thanks,
Rafael
Mika Westerberg Jan. 30, 2017, 9:33 a.m. UTC | #3
On Mon, Jan 30, 2017 at 09:28:09AM +0100, Rafael J. Wysocki wrote:
> On Mon, Jan 30, 2017 at 9:18 AM, Thierry Reding
> <thierry.reding@gmail.com> wrote:
> > On Sun, Jan 22, 2017 at 05:14:09PM +0100, Hans de Goede wrote:
> >> On x86 we do not have devicetree to link the PWM controller and
> >> the display controller together. So someone needs to call
> >> pwm_add_table() to create the link, so that the i915 driver's
> >> pwm_get(dev, "pwm_backlight") call returns the lpss' pwm0.
> >>
> >> The PWM subsystem does not want to have pwm_add_table() calls
> >> directly in PWM drivers (this leads to probe ordering issues),
> >> so lets do it here since the acpi-lpss code is always builtin.
> >>
> >> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> >> Acked-by: Thierry Reding <thierry.reding@gmail.com>
> >> ---
> >> Changes in v2:
> >> -Set new pwm_lookup module_name field in the table
> >> ---
> >>  drivers/acpi/acpi_lpss.c | 13 +++++++++++++
> >>  1 file changed, 13 insertions(+)
> >
> > Rafael, do you mind if I take this through the PWM tree to resolve the
> > build-time dependency?
> 
> No, I don't, please go ahead, unless Mika/Andy see any problems in it.

No problems from my side - looks good.
Thierry Reding Jan. 30, 2017, 9:47 a.m. UTC | #4
On Mon, Jan 30, 2017 at 11:33:10AM +0200, Mika Westerberg wrote:
> On Mon, Jan 30, 2017 at 09:28:09AM +0100, Rafael J. Wysocki wrote:
> > On Mon, Jan 30, 2017 at 9:18 AM, Thierry Reding
> > <thierry.reding@gmail.com> wrote:
> > > On Sun, Jan 22, 2017 at 05:14:09PM +0100, Hans de Goede wrote:
> > >> On x86 we do not have devicetree to link the PWM controller and
> > >> the display controller together. So someone needs to call
> > >> pwm_add_table() to create the link, so that the i915 driver's
> > >> pwm_get(dev, "pwm_backlight") call returns the lpss' pwm0.
> > >>
> > >> The PWM subsystem does not want to have pwm_add_table() calls
> > >> directly in PWM drivers (this leads to probe ordering issues),
> > >> so lets do it here since the acpi-lpss code is always builtin.
> > >>
> > >> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> > >> Acked-by: Thierry Reding <thierry.reding@gmail.com>
> > >> ---
> > >> Changes in v2:
> > >> -Set new pwm_lookup module_name field in the table
> > >> ---
> > >>  drivers/acpi/acpi_lpss.c | 13 +++++++++++++
> > >>  1 file changed, 13 insertions(+)
> > >
> > > Rafael, do you mind if I take this through the PWM tree to resolve the
> > > build-time dependency?
> > 
> > No, I don't, please go ahead, unless Mika/Andy see any problems in it.
> 
> No problems from my side - looks good.

I've pulled this into a separate branch that also contains the
prerequisites, so if you ever need this in ACPI, I can provide a stable
branch or tag.

Thanks,
Thierry
diff mbox

Patch

diff --git a/drivers/acpi/acpi_lpss.c b/drivers/acpi/acpi_lpss.c
index 8ea836c..794be64 100644
--- a/drivers/acpi/acpi_lpss.c
+++ b/drivers/acpi/acpi_lpss.c
@@ -20,6 +20,7 @@ 
 #include <linux/platform_data/clk-lpss.h>
 #include <linux/pm_domain.h>
 #include <linux/pm_runtime.h>
+#include <linux/pwm.h>
 #include <linux/delay.h>
 
 #include "internal.h"
@@ -154,6 +155,17 @@  static void byt_i2c_setup(struct lpss_private_data *pdata)
 	writel(0, pdata->mmio_base + LPSS_I2C_ENABLE);
 }
 
+/* BSW PWM used for backlight control by the i915 driver */
+static struct pwm_lookup bsw_pwm_lookup[] = {
+	PWM_LOOKUP_MODNAME("80862288:00", 0, "0000:00:02.0", "pwm_backlight",
+			   0, PWM_POLARITY_NORMAL, "pwm-lpss-platform"),
+};
+
+static void bsw_pwm_setup(struct lpss_private_data *pdata)
+{
+	pwm_add_table(bsw_pwm_lookup, ARRAY_SIZE(bsw_pwm_lookup));
+}
+
 static const struct lpss_device_desc lpt_dev_desc = {
 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR,
 	.prv_offset = 0x800,
@@ -191,6 +203,7 @@  static const struct lpss_device_desc byt_pwm_dev_desc = {
 
 static const struct lpss_device_desc bsw_pwm_dev_desc = {
 	.flags = LPSS_SAVE_CTX | LPSS_NO_D3_DELAY,
+	.setup = bsw_pwm_setup,
 };
 
 static const struct lpss_device_desc byt_uart_dev_desc = {