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[XEN PATCH v2 1/3] drivers: char: address violation of MISRA C Rule 20.7

Nicola Vetrini posted 3 patches 1 year, 9 months ago
There is a newer version of this series
[XEN PATCH v2 1/3] drivers: char: address violation of MISRA C Rule 20.7
Posted by Nicola Vetrini 1 year, 9 months ago 
MISRA C Rule 20.7 states: "Expressions resulting from the expansion
of macro parameters shall be enclosed in parentheses". Therefore, some
macro definitions should gain additional parentheses to ensure that all
current and future users will be safe with respect to expansions that
can possibly alter the semantics of the passed-in macro parameter.

No functional chage.

Signed-off-by: Nicola Vetrini <nicola.vetrini@bugseng.com>
---
Changes in v2:
- drop excess parentheses from val parameter.
---
 xen/drivers/char/omap-uart.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/xen/drivers/char/omap-uart.c b/xen/drivers/char/omap-uart.c
index 03b5b66e7acb..e0128225f927 100644
--- a/xen/drivers/char/omap-uart.c
+++ b/xen/drivers/char/omap-uart.c
@@ -48,8 +48,9 @@
 /* System configuration register */
 #define UART_OMAP_SYSC_DEF_CONF   0x0d   /* autoidle mode, wakeup is enabled */
 
-#define omap_read(uart, off)       readl((uart)->regs + (off<<REG_SHIFT))
-#define omap_write(uart, off, val) writel((val), (uart)->regs + (off<<REG_SHIFT))
+#define omap_read(uart, off)       readl((uart)->regs + ((off) << REG_SHIFT))
+#define omap_write(uart, off, val) writel(val, (uart)->regs + \
+                                               ((off) << REG_SHIFT))
 
 static struct omap_uart {
     u32 baud, clock_hz, data_bits, parity, stop_bits, fifo_size;
-- 
2.34.1
Re: [XEN PATCH v2 1/3] drivers: char: address violation of MISRA C Rule 20.7
Posted by Stefano Stabellini 1 year, 9 months ago 
On Tue, 30 Apr 2024, Nicola Vetrini wrote:
> MISRA C Rule 20.7 states: "Expressions resulting from the expansion
> of macro parameters shall be enclosed in parentheses". Therefore, some
> macro definitions should gain additional parentheses to ensure that all
> current and future users will be safe with respect to expansions that
> can possibly alter the semantics of the passed-in macro parameter.
> 
> No functional chage.
> 
> Signed-off-by: Nicola Vetrini <nicola.vetrini@bugseng.com>

Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>


> ---
> Changes in v2:
> - drop excess parentheses from val parameter.
> ---
>  xen/drivers/char/omap-uart.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/xen/drivers/char/omap-uart.c b/xen/drivers/char/omap-uart.c
> index 03b5b66e7acb..e0128225f927 100644
> --- a/xen/drivers/char/omap-uart.c
> +++ b/xen/drivers/char/omap-uart.c
> @@ -48,8 +48,9 @@
>  /* System configuration register */
>  #define UART_OMAP_SYSC_DEF_CONF   0x0d   /* autoidle mode, wakeup is enabled */
>  
> -#define omap_read(uart, off)       readl((uart)->regs + (off<<REG_SHIFT))
> -#define omap_write(uart, off, val) writel((val), (uart)->regs + (off<<REG_SHIFT))
> +#define omap_read(uart, off)       readl((uart)->regs + ((off) << REG_SHIFT))
> +#define omap_write(uart, off, val) writel(val, (uart)->regs + \
> +                                               ((off) << REG_SHIFT))

the alignment looks off but could be fixed on commit


>  static struct omap_uart {
>      u32 baud, clock_hz, data_bits, parity, stop_bits, fifo_size;
Re: [XEN PATCH v2 1/3] drivers: char: address violation of MISRA C Rule 20.7
Posted by Nicola Vetrini 1 year, 9 months ago 
On 2024-05-01 21:57, Stefano Stabellini wrote:
> On Tue, 30 Apr 2024, Nicola Vetrini wrote:
>> MISRA C Rule 20.7 states: "Expressions resulting from the expansion
>> of macro parameters shall be enclosed in parentheses". Therefore, some
>> macro definitions should gain additional parentheses to ensure that 
>> all
>> current and future users will be safe with respect to expansions that
>> can possibly alter the semantics of the passed-in macro parameter.
>> 
>> No functional chage.
>> 
>> Signed-off-by: Nicola Vetrini <nicola.vetrini@bugseng.com>
> 
> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
> 
> 
>> ---
>> Changes in v2:
>> - drop excess parentheses from val parameter.
>> ---
>>  xen/drivers/char/omap-uart.c | 5 +++--
>>  1 file changed, 3 insertions(+), 2 deletions(-)
>> 
>> diff --git a/xen/drivers/char/omap-uart.c 
>> b/xen/drivers/char/omap-uart.c
>> index 03b5b66e7acb..e0128225f927 100644
>> --- a/xen/drivers/char/omap-uart.c
>> +++ b/xen/drivers/char/omap-uart.c
>> @@ -48,8 +48,9 @@
>>  /* System configuration register */
>>  #define UART_OMAP_SYSC_DEF_CONF   0x0d   /* autoidle mode, wakeup is 
>> enabled */
>> 
>> -#define omap_read(uart, off)       readl((uart)->regs + 
>> (off<<REG_SHIFT))
>> -#define omap_write(uart, off, val) writel((val), (uart)->regs + 
>> (off<<REG_SHIFT))
>> +#define omap_read(uart, off)       readl((uart)->regs + ((off) << 
>> REG_SHIFT))
>> +#define omap_write(uart, off, val) writel(val, (uart)->regs + \
>> +                                               ((off) << REG_SHIFT))
> 
> the alignment looks off but could be fixed on commit
> 

Can you clarify what you mean here? I aligned readl and writeln and the 
operands in writel to avoid the line being too long.

Thanks,

-- 
Nicola Vetrini, BSc
Software Engineer, BUGSENG srl (https://bugseng.com)
Re: [XEN PATCH v2 1/3] drivers: char: address violation of MISRA C Rule 20.7
Posted by Jan Beulich 1 year, 9 months ago 
On 03.05.2024 09:29, Nicola Vetrini wrote:
> On 2024-05-01 21:57, Stefano Stabellini wrote:
>> On Tue, 30 Apr 2024, Nicola Vetrini wrote:
>>> MISRA C Rule 20.7 states: "Expressions resulting from the expansion
>>> of macro parameters shall be enclosed in parentheses". Therefore, some
>>> macro definitions should gain additional parentheses to ensure that 
>>> all
>>> current and future users will be safe with respect to expansions that
>>> can possibly alter the semantics of the passed-in macro parameter.
>>>
>>> No functional chage.
>>>
>>> Signed-off-by: Nicola Vetrini <nicola.vetrini@bugseng.com>
>>
>> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
>>
>>
>>> ---
>>> Changes in v2:
>>> - drop excess parentheses from val parameter.
>>> ---
>>>  xen/drivers/char/omap-uart.c | 5 +++--
>>>  1 file changed, 3 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/xen/drivers/char/omap-uart.c 
>>> b/xen/drivers/char/omap-uart.c
>>> index 03b5b66e7acb..e0128225f927 100644
>>> --- a/xen/drivers/char/omap-uart.c
>>> +++ b/xen/drivers/char/omap-uart.c
>>> @@ -48,8 +48,9 @@
>>>  /* System configuration register */
>>>  #define UART_OMAP_SYSC_DEF_CONF   0x0d   /* autoidle mode, wakeup is 
>>> enabled */
>>>
>>> -#define omap_read(uart, off)       readl((uart)->regs + 
>>> (off<<REG_SHIFT))
>>> -#define omap_write(uart, off, val) writel((val), (uart)->regs + 
>>> (off<<REG_SHIFT))
>>> +#define omap_read(uart, off)       readl((uart)->regs + ((off) << 
>>> REG_SHIFT))
>>> +#define omap_write(uart, off, val) writel(val, (uart)->regs + \
>>> +                                               ((off) << REG_SHIFT))
>>
>> the alignment looks off but could be fixed on commit
>>
> 
> Can you clarify what you mean here? I aligned readl and writeln and the 
> operands in writel to avoid the line being too long.

#define omap_write(uart, off, val) writel(val, \
                                          (uart)->regs + ((off) << REG_SHIFT))

The main point being that before you start splitting an argument following
another one on the same line, you'd move that argument to a new line.

Jan
Re: [XEN PATCH v2 1/3] drivers: char: address violation of MISRA C Rule 20.7
Posted by Nicola Vetrini 1 year, 9 months ago 
On 2024-05-03 12:10, Jan Beulich wrote:
> On 03.05.2024 09:29, Nicola Vetrini wrote:
>> On 2024-05-01 21:57, Stefano Stabellini wrote:
>>> On Tue, 30 Apr 2024, Nicola Vetrini wrote:
>>>> MISRA C Rule 20.7 states: "Expressions resulting from the expansion
>>>> of macro parameters shall be enclosed in parentheses". Therefore, 
>>>> some
>>>> macro definitions should gain additional parentheses to ensure that
>>>> all
>>>> current and future users will be safe with respect to expansions 
>>>> that
>>>> can possibly alter the semantics of the passed-in macro parameter.
>>>> 
>>>> No functional chage.
>>>> 
>>>> Signed-off-by: Nicola Vetrini <nicola.vetrini@bugseng.com>
>>> 
>>> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
>>> 
>>> 
>>>> ---
>>>> Changes in v2:
>>>> - drop excess parentheses from val parameter.
>>>> ---
>>>>  xen/drivers/char/omap-uart.c | 5 +++--
>>>>  1 file changed, 3 insertions(+), 2 deletions(-)
>>>> 
>>>> diff --git a/xen/drivers/char/omap-uart.c
>>>> b/xen/drivers/char/omap-uart.c
>>>> index 03b5b66e7acb..e0128225f927 100644
>>>> --- a/xen/drivers/char/omap-uart.c
>>>> +++ b/xen/drivers/char/omap-uart.c
>>>> @@ -48,8 +48,9 @@
>>>>  /* System configuration register */
>>>>  #define UART_OMAP_SYSC_DEF_CONF   0x0d   /* autoidle mode, wakeup 
>>>> is
>>>> enabled */
>>>> 
>>>> -#define omap_read(uart, off)       readl((uart)->regs +
>>>> (off<<REG_SHIFT))
>>>> -#define omap_write(uart, off, val) writel((val), (uart)->regs +
>>>> (off<<REG_SHIFT))
>>>> +#define omap_read(uart, off)       readl((uart)->regs + ((off) <<
>>>> REG_SHIFT))
>>>> +#define omap_write(uart, off, val) writel(val, (uart)->regs + \
>>>> +                                               ((off) << 
>>>> REG_SHIFT))
>>> 
>>> the alignment looks off but could be fixed on commit
>>> 
>> 
>> Can you clarify what you mean here? I aligned readl and writeln and 
>> the
>> operands in writel to avoid the line being too long.
> 
> #define omap_write(uart, off, val) writel(val, \
>                                           (uart)->regs + ((off) << 
> REG_SHIFT))
> 
> The main point being that before you start splitting an argument 
> following
> another one on the same line, you'd move that argument to a new line.
> 
> Jan

Oh, ok. Didn't think of that. Thanks, can amend it

-- 
Nicola Vetrini, BSc
Software Engineer, BUGSENG srl (https://bugseng.com)

Patchew 2.1-devel-b67e4c2

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