Re: [PATCH 1/2] mfd: rtsx: add func to split u32 into register

[敬锐]

On 11/27/2014 11:23 PM, Dan Carpenter wrote:
>> +static inline void rtsx_pci_write_be32(struct rtsx_pcr *pcr, u16 reg, u32 val)
>> >+{
>> >+	rtsx_pci_add_cmd(pcr, WRITE_REG_CMD, reg,     0xFF, val >> 24);
>> >+	rtsx_pci_add_cmd(pcr, WRITE_REG_CMD, reg + 1, 0xFF, val >> 16);
>> >+	rtsx_pci_add_cmd(pcr, WRITE_REG_CMD, reg + 2, 0xFF, val >> 8);
>> >+	rtsx_pci_add_cmd(pcr, WRITE_REG_CMD, reg + 3, 0xFF, val);
> This assumes the cpu is little endian.  First convert to big endian
> using cpu_to_be32() and then write it out.
>
> 	__be32 be_val = cpu_to_be32()
>
> 	rtsx_pci_add_cmd(pcr, WRITE_REG_CMD, reg,     0xFF, be_val);
> 	rtsx_pci_add_cmd(pcr, WRITE_REG_CMD, reg + 1, 0xFF, be_val >> 8);
> 	rtsx_pci_add_cmd(pcr, WRITE_REG_CMD, reg + 2, 0xFF, be_val >> 16);
> 	rtsx_pci_add_cmd(pcr, WRITE_REG_CMD, reg + 3, 0xFF, be_val >> 24);
>
> (Written hurredly in my mail client.  May be wrong).
>
I think we better not use cpu_to_be32() here, leave the work to caller
may be better.

eg, in sd_ops.c the cmd.arg is constructed bit by bit, we can put the right
byte to the right register by shift, so the endian check is not need.N?叉??y??b??千v??藓{.n???{?赙zXФ?塄}?财??j:+v???赙zZ+€?zf＂?????i????ア??璀??撷f?^j谦y??@A?囤?0鹅h??i