[PATCH v2 2/2] tty: serial: samsung: Clean-up selection of number of available UARTs

Abhilash Kesavan kesavan.abhilash at gmail.com
Thu Oct 30 19:36:02 PDT 2014


Hi Kukjin,

On Tue, Oct 28, 2014 at 5:56 PM, Abhilash Kesavan
<kesavan.abhilash at gmail.com> wrote:
> Hi Kukjin
>
> On Tue, Oct 28, 2014 at 4:01 PM, Kukjin Kim <kgene at kernel.org> wrote:
>> Abhilash Kesavan wrote:
>>>
>> Hi,
>>
>> Sorry for late response.
>>
>>> Remove symbols SERIAL_SAMSUNG_UARTS_4 and SERIAL_SAMSUNG_UARTS which
>>> select the number of UART ports available on the SoC. Replace the usage
>>> of SERIAL_SAMSUNG_UARTS in the serial driver with the maximum number of
>>
>> Well, as you know the number of uart ports are different on each Samsung SoCs
>> so I don't think just using maximum number of uart ports are possible for new
>> exynos7 SoC at this moment.
>
> Thanks for the review.
> The main reason for me sending this patch was so that we may be able
> to re-use the serial driver on arm64 based Exynos7 too. The two
> symbols mentioned above which depend on PLAT_SAMSUNG prevent this. I
> initially sent a patch which changed the dependency to SERIAL_SAMSUNG
> for these 2 symbols. However, Tomasz suggested that a clean-up of
> these two symbols would be a better option.
>
> Please see the discussion of the previous version here:
> https://lkml.org/lkml/2014/9/29/702
>
> Can you please let me know if the previous version is acceptable ?

Kukjin, can you please indicate the approach you would like me to
take. Without this serial support is blocked on Exynos7.

Thanks,
Abhilash
>
>>
>>> UART ports possible. Removal of these symbols also helps in Exynos7
>>> serial enablement.
>>>
>>> Signed-off-by: Abhilash Kesavan <a.kesavan at samsung.com>
>>> Reviewed-by: Tomasz Figa <tomasz.figa at gmail.com>
>>> Cc: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
>>> ---
>>>  drivers/tty/serial/Kconfig   |   16 ----------------
>>>  drivers/tty/serial/samsung.c |   11 +++--------
>>>  drivers/tty/serial/samsung.h |    5 ++++-
>>>  3 files changed, 7 insertions(+), 25 deletions(-)
>>>
>>> diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
>>> index 81f6ee7..9fc9092 100644
>>> --- a/drivers/tty/serial/Kconfig
>>> +++ b/drivers/tty/serial/Kconfig
>>> @@ -247,22 +247,6 @@ config SERIAL_SAMSUNG
>>>         provide all of these ports, depending on how the serial port
>>>         pins are configured.
>>>
>>> -config SERIAL_SAMSUNG_UARTS_4
>>> -     bool
>>> -     depends on PLAT_SAMSUNG
>>> -     default y if !(CPU_S3C2410 || CPU_S3C2412 || CPU_S3C2440 || CPU_S3C2442)
>>> -     help
>>> -       Internal node for the common case of 4 Samsung compatible UARTs
>>> -
>>> -config SERIAL_SAMSUNG_UARTS
>>> -     int
>>> -     depends on PLAT_SAMSUNG
>>> -     default 4 if SERIAL_SAMSUNG_UARTS_4 || CPU_S3C2416
>>> -     default 3
>>> -     help
>>> -       Select the number of available UART ports for the Samsung S3C
>>> -       serial driver
>>> -
>>>  config SERIAL_SAMSUNG_DEBUG
>>>       bool "Samsung SoC serial debug"
>>>       depends on SERIAL_SAMSUNG && DEBUG_LL
>>> diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c
>>> index c78f43a..ba04c6d 100644
>>> --- a/drivers/tty/serial/samsung.c
>>> +++ b/drivers/tty/serial/samsung.c
>>> @@ -962,14 +962,14 @@ static struct uart_ops s3c24xx_serial_ops = {
>>>  static struct uart_driver s3c24xx_uart_drv = {
>>>       .owner          = THIS_MODULE,
>>>       .driver_name    = "s3c2410_serial",
>>> -     .nr             = CONFIG_SERIAL_SAMSUNG_UARTS,
>>> +     .nr             = MAX_SAMSUNG_UARTS,
>>>       .cons           = S3C24XX_SERIAL_CONSOLE,
>>>       .dev_name       = S3C24XX_SERIAL_NAME,
>>>       .major          = S3C24XX_SERIAL_MAJOR,
>>>       .minor          = S3C24XX_SERIAL_MINOR,
>>>  };
>>>
>>> -static struct s3c24xx_uart_port s3c24xx_serial_ports[CONFIG_SERIAL_SAMSUNG_UARTS] = {
>>> +static struct s3c24xx_uart_port s3c24xx_serial_ports[MAX_SAMSUNG_UARTS] = {
>>>       [0] = {
>>>               .port = {
>>>                       .lock           = __SPIN_LOCK_UNLOCKED(s3c24xx_serial_ports[0].port.lock),
>>> @@ -992,8 +992,6 @@ static struct s3c24xx_uart_port s3c24xx_serial_ports[CONFIG_SERIAL_SAMSUNG_UARTS
>>>                       .line           = 1,
>>>               }
>>>       },
>>> -#if CONFIG_SERIAL_SAMSUNG_UARTS > 2
>>> -
>>>       [2] = {
>>>               .port = {
>>>                       .lock           = __SPIN_LOCK_UNLOCKED(s3c24xx_serial_ports[2].port.lock),
>>> @@ -1005,8 +1003,6 @@ static struct s3c24xx_uart_port s3c24xx_serial_ports[CONFIG_SERIAL_SAMSUNG_UARTS
>>>                       .line           = 2,
>>>               }
>>>       },
>>> -#endif
>>> -#if CONFIG_SERIAL_SAMSUNG_UARTS > 3
>>>       [3] = {
>>>               .port = {
>>>                       .lock           = __SPIN_LOCK_UNLOCKED(s3c24xx_serial_ports[3].port.lock),
>>> @@ -1018,7 +1014,6 @@ static struct s3c24xx_uart_port s3c24xx_serial_ports[CONFIG_SERIAL_SAMSUNG_UARTS
>>>                       .line           = 3,
>>>               }
>>>       }
>>> -#endif
>>>  };
>>>
>>>  /* s3c24xx_serial_resetport
>>> @@ -1590,7 +1585,7 @@ s3c24xx_serial_console_setup(struct console *co, char *options)
>>>
>>>       /* is this a valid port */
>>>
>>> -     if (co->index == -1 || co->index >= CONFIG_SERIAL_SAMSUNG_UARTS)
>>> +     if (co->index == -1 || co->index >= MAX_SAMSUNG_UARTS)
>>
>> If we use max number, second condition is not required...
>>
>>>               co->index = 0;
>>>
>>>       port = &s3c24xx_serial_ports[co->index].port;
>>> diff --git a/drivers/tty/serial/samsung.h b/drivers/tty/serial/samsung.h
>>> index eb071dd..484b49e 100644
>>> --- a/drivers/tty/serial/samsung.h
>>> +++ b/drivers/tty/serial/samsung.h
>>> @@ -1,6 +1,9 @@
>>>  #ifndef __SAMSUNG_H
>>>  #define __SAMSUNG_H
>>>
>>> +/* Maximum UART ports available */
>>> +#define MAX_SAMSUNG_UARTS       4
>>
>> If there is a Samsung SoC having 5 UARTS, we need to update?
>
> Yes, we would need to update the MAX_SAMSUNG_UARTS define for a newer
> SoC with 5 uart ports but even without this patch we would have to
> modify the SERIAL_SAMSUNG_UARTS symbol to handle 5 ports.
>>
>> And hmm...maybe we need to keep the useless array sometimes...
>
> Yes, for the 24xx series with 3 uart ports we would.
>
> Regards,
> Abhilash
>>
>>> +
>>>  /*
>>>   * Driver for Samsung SoC onboard UARTs.
>>>   *
>>> @@ -38,7 +41,7 @@ struct s3c24xx_uart_info {
>>>  struct s3c24xx_serial_drv_data {
>>>       struct s3c24xx_uart_info        *info;
>>>       struct s3c2410_uartcfg          *def_cfg;
>>> -     unsigned int                    fifosize[CONFIG_SERIAL_SAMSUNG_UARTS];
>>> +     unsigned int                    fifosize[MAX_SAMSUNG_UARTS];
>>>  };
>>>
>>>  struct s3c24xx_uart_port {
>>> --
>>> 1.7.9.5
>>
>>
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