Let's take an example, cmd.arg = ((ocr & 0xFF8000) != 0) << 8 | test_pattern; using "TP" name test_pattern for simplication , when we call: rtsx_pci_write_be32(pcr, SD_CMD1, cmd->arg); we should make sure TP write to SD_CMD4. If on "be" platform, then cpu_to_be32() do nothing, and TP is write to SD_CMD1, in this case, it is wrong. BR, micky. On 11/27/2014 11:23 PM, Dan Carpenter wrote: > On Thu, Nov 27, 2014 at 10:53:58AM +0800, micky_ching@xxxxxxxxxxxxxx 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). > >> +} >> + >> +static inline void rtsx_pci_write_le32(struct rtsx_pcr *pcr, u16 reg, u32 val) >> +{ >> + rtsx_pci_add_cmd(pcr, WRITE_REG_CMD, reg, 0xFF, val); >> + rtsx_pci_add_cmd(pcr, WRITE_REG_CMD, reg + 1, 0xFF, val >> 8); >> + rtsx_pci_add_cmd(pcr, WRITE_REG_CMD, reg + 2, 0xFF, val >> 16); >> + rtsx_pci_add_cmd(pcr, WRITE_REG_CMD, reg + 3, 0xFF, val >> 24); >> +} > We don't have a user for rtsx_pci_write_le32() so don't add it. > > regards, > dan carpenter ?韬{.n?????%??檩??w?{.n???{炳i?)?骅w*jg????????G??⒏⒎?:+v????????????"??????