[PATCH 4/4] tty/serial: sh-sci: remove uneeded IS_ERR_OR_NULL calls
Linus Walleij
linus.walleij at linaro.org
Thu Mar 16 08:18:52 PDT 2017
On Mon, Mar 6, 2017 at 11:02 AM, Uwe Kleine-König
<u.kleine-koenig at pengutronix.de> wrote:
> On Mon, Mar 06, 2017 at 10:53:27AM +0100, Geert Uytterhoeven wrote:
>> On Mon, Mar 6, 2017 at 10:30 AM, Uwe Kleine-König
>> > I wouldn't want to code this in each driver (something like:
>> >
>> > if (IS_ENABLED(GPIOLIB) || device_is_instantiated_by_dt(dev) || device_is_instantiated_by_acpi(dev))
>> > gpios = mctrl_gpio_init(...);
>> > else
>> > gpios = NULL;
>> >
>> > ). Putting this into GPIOLIB is the right approach, and so this is
>> > another argument for HALFGPIOLIB. This would fix mctrl_gpio_init en
>> > passant.
>>
>> Do we have platforms where DT=y || ACPI=y, but GPIOLIB=n?
>> Ah, x86 ;-)
>
> Yeah, and I think rm -r arch/x86 won't be acceptable :-) I assume you
> can also configure some arm or powerpc systems without GPIOLIB.
>
>> Anyway, for sh-sci.c, platforms either have DT and GPIOLIB, or they do not
>> need mctrl-gpio.
>
> So we're in agreement now that HALFGPIOLIB is the way to go?
> Linus, what do you think?
OK modem lines over GPIO.
So the problem is that GPIOLIB is needed (obviously) for mctrl_gpio_init() to
work properly, and then there are some stubs in
drivers/tty/serial/serial_mctrl_gpio.h
for !GPIOLIB.
And this whole discussion is all about that !GPIOLIB case really,
whether DT, ACPI, SFI or board files machine data is used doesn't
really matter.
We're talking about:
> git grep mctrl_gpio_init
drivers/tty/serial/atmel_serial.c: atmel_port->gpios =
mctrl_gpio_init(&atmel_port->uart, 0);
drivers/tty/serial/clps711x.c: s->gpios =
mctrl_gpio_init_noauto(&pdev->dev, 0);
drivers/tty/serial/etraxfs-uart.c: up->gpios =
mctrl_gpio_init_noauto(&pdev->dev, 0);
drivers/tty/serial/imx.c: sport->gpios = mctrl_gpio_init(&sport->port, 0);
drivers/tty/serial/mxs-auart.c: s->gpios = mctrl_gpio_init_noauto(dev, 0);
drivers/tty/serial/sh-sci.c: sciport->gpios =
mctrl_gpio_init(&sciport->port, 0);
Atmel, ARM, ETRAX, ARM, ARM, Super-H, all have GPIOLIB.
Right now no x86, correct?
They actually all even do things like this in Kconfig:
config SERIAL_ATMEL
(...)
select SERIAL_MCTRL_GPIO if GPIOLIB
What stops us from removing all the stubs in
drivers/tty/serial/serial_mctrl_gpio.h
and just make SERIAL_MCTRL_GPIO depends on GPIOLIB?
>From 2ecc70acc510784d953add707f2a5acfebe484c2 Mon Sep 17 00:00:00 2001
From: Linus Walleij <linus.walleij at linaro.org>
Date: Thu, 16 Mar 2017 16:18:21 +0100
Subject: [PATCH] stab at mctrl
Signed-off-by: Linus Walleij <linus.walleij at linaro.org>
---
drivers/tty/serial/Kconfig | 1 +
drivers/tty/serial/serial_mctrl_gpio.h | 55 ----------------------------------
2 files changed, 1 insertion(+), 55 deletions(-)
diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
index 6117ac8da48f..39833d009c18 100644
--- a/drivers/tty/serial/Kconfig
+++ b/drivers/tty/serial/Kconfig
@@ -1681,5 +1681,6 @@ endmenu
config SERIAL_MCTRL_GPIO
tristate
+ depends on GPIOLIB
endif # TTY
diff --git a/drivers/tty/serial/serial_mctrl_gpio.h
b/drivers/tty/serial/serial_mctrl_gpio.h
index fa000bcff217..ba8f8e531d56 100644
--- a/drivers/tty/serial/serial_mctrl_gpio.h
+++ b/drivers/tty/serial/serial_mctrl_gpio.h
@@ -40,8 +40,6 @@ enum mctrl_gpio_idx {
*/
struct mctrl_gpios;
-#ifdef CONFIG_GPIOLIB
-
/*
* Set state of the modem control output lines via GPIOs.
*/
@@ -101,57 +99,4 @@ void mctrl_gpio_enable_ms(struct mctrl_gpios *gpios);
*/
void mctrl_gpio_disable_ms(struct mctrl_gpios *gpios);
-#else /* GPIOLIB */
-
-static inline
-void mctrl_gpio_set(struct mctrl_gpios *gpios, unsigned int mctrl)
-{
-}
-
-static inline
-unsigned int mctrl_gpio_get(struct mctrl_gpios *gpios, unsigned int *mctrl)
-{
- return *mctrl;
-}
-
-static inline unsigned int
-mctrl_gpio_get_outputs(struct mctrl_gpios *gpios, unsigned int *mctrl)
-{
- return *mctrl;
-}
-
-static inline
-struct gpio_desc *mctrl_gpio_to_gpiod(struct mctrl_gpios *gpios,
- enum mctrl_gpio_idx gidx)
-{
- return ERR_PTR(-ENOSYS);
-}
-
-static inline
-struct mctrl_gpios *mctrl_gpio_init(struct uart_port *port, unsigned int idx)
-{
- return ERR_PTR(-ENOSYS);
-}
-
-static inline
-struct mctrl_gpios *mctrl_gpio_init_noauto(struct device *dev,
unsigned int idx)
-{
- return ERR_PTR(-ENOSYS);
-}
-
-static inline
-void mctrl_gpio_free(struct device *dev, struct mctrl_gpios *gpios)
-{
-}
-
-static inline void mctrl_gpio_enable_ms(struct mctrl_gpios *gpios)
-{
-}
-
-static inline void mctrl_gpio_disable_ms(struct mctrl_gpios *gpios)
-{
-}
-
-#endif /* GPIOLIB */
-
#endif
--
2.9.3
Yours,
Linus Walleij
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