Re: [PATCH 06/44] staging: spmi: hisi-spmi-controller: use le32 macros where needed

From: Joe Perches
Date: Wed Aug 12 2020 - 12:21:59 EST


On Wed, 2020-08-12 at 17:56 +0200, Mauro Carvalho Chehab wrote:
> Instead of manually using bswap_32(), just use the
> le32 macros.

Are you certain this code will now work on any endian cpu?

Maybe just use __swab32 instead

> diff --git a/drivers/staging/hikey9xx/hisi-spmi-controller.c b/drivers/staging/hikey9xx/hisi-spmi-controller.c
[]
> @@ -43,11 +42,6 @@
> #define SPMI_APB_SPMI_CMD_TYPE_OFFSET 24
> #define SPMI_APB_SPMI_CMD_LENGTH_OFFSET 20
>
> -#define bswap_32(X) \
> - ((((u32)(X) & 0xff000000) >> 24) | \
> - (((u32)(X) & 0x00ff0000) >> 8) | \
> - (((u32)(X) & 0x0000ff00) << 8) | \
> - (((u32)(X) & 0x000000ff) << 24))
> #define SPMI_APB_SPMI_CMD_SLAVEID_OFFSET 16
> #define SPMI_APB_SPMI_CMD_ADDR_OFFSET 0
>
> @@ -179,14 +173,15 @@ static int spmi_read_cmd(struct spmi_controller *ctrl,
>
> writel(cmd, spmi_controller->base + chnl_ofst + SPMI_APB_SPMI_CMD_BASE_ADDR);
>
> - rc = spmi_controller_wait_for_done(spmi_controller, spmi_controller->base, sid, addr);
> + rc = spmi_controller_wait_for_done(spmi_controller,
> + spmi_controller->base, sid, addr);
> if (rc)
> goto done;
>
> i = 0;
> do {
> data = readl(spmi_controller->base + chnl_ofst + SPMI_SLAVE_OFFSET * sid + SPMI_APB_SPMI_RDATA0_BASE_ADDR + i * SPMI_PER_DATAREG_BYTE);
> - data = bswap_32(data);
> + data = be32_to_cpu((__be32)data);
> if ((bc - i * SPMI_PER_DATAREG_BYTE) >> 2) {
> memcpy(buf, &data, sizeof(data));
> buf += sizeof(data);
> @@ -210,8 +205,7 @@ static int spmi_write_cmd(struct spmi_controller *ctrl,
> {
> struct spmi_controller_dev *spmi_controller = dev_get_drvdata(&ctrl->dev);
> unsigned long flags;
> - u32 cmd;
> - u32 data = 0;
> + u32 cmd, data;
> int rc;
> u32 chnl_ofst = SPMI_CHANNEL_OFFSET * spmi_controller->channel;
> u8 op_code, i;
> @@ -246,7 +240,7 @@ static int spmi_write_cmd(struct spmi_controller *ctrl,
>
> i = 0;
> do {
> - memset(&data, 0, sizeof(data));
> + data = 0;
> if ((bc - i * SPMI_PER_DATAREG_BYTE) >> 2) {
> memcpy(&data, buf, sizeof(data));
> buf += sizeof(data);
> @@ -255,8 +249,8 @@ static int spmi_write_cmd(struct spmi_controller *ctrl,
> buf += (bc % SPMI_PER_DATAREG_BYTE);
> }
>
> - data = bswap_32(data);
> - writel(data, spmi_controller->base + chnl_ofst + SPMI_APB_SPMI_WDATA0_BASE_ADDR + SPMI_PER_DATAREG_BYTE * i);
> + writel((u32)cpu_to_be32(data),
> + spmi_controller->base + chnl_ofst + SPMI_APB_SPMI_WDATA0_BASE_ADDR + SPMI_PER_DATAREG_BYTE * i);
> i++;
> } while (bc > i * SPMI_PER_DATAREG_BYTE);
>