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

Abhilash Kesavan kesavan.abhilash at gmail.com
Mon Nov 3 00:21:17 PST 2014


Hello Kukjin,

On Fri, Oct 31, 2014 at 8:06 AM, Abhilash Kesavan
<kesavan.abhilash at gmail.com> wrote:
> 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.

Gentle reminder on this.

Abhilash
>
> 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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