On 21 November 2014 at 15:46, Barry Song <21cnbao@xxxxxxxxx> wrote:
> From: Minda Chen <Minda.Chen@xxxxxxx>
>
> According to the SD card spec, Add a manual tuning command function
> for SDR104/HS200 by sending command 19 or command 21 to read data
> and compare with the tuning block pattern.
>
> this patch will help to decrease some platform private codes in
> SDHCI platform_execute_tuning() callbacks.
>
> Signed-off-by: Minda Chen <Minda.Chen@xxxxxxx>
> Signed-off-by: Barry Song <Baohua.Song@xxxxxxx>
> ---
> drivers/mmc/core/mmc_ops.c | 65 ++++++++++++++++++++++++++++++++++++++++++++++
> include/linux/mmc/core.h | 1 +
> 2 files changed, 66 insertions(+)
>
> diff --git a/drivers/mmc/core/mmc_ops.c b/drivers/mmc/core/mmc_ops.c
> index 7911e05..ecc7789 100644
> --- a/drivers/mmc/core/mmc_ops.c
> +++ b/drivers/mmc/core/mmc_ops.c
> @@ -543,6 +543,71 @@ int mmc_switch(struct mmc_card *card, u8 set, u8 index, u8 value,
> }
> EXPORT_SYMBOL_GPL(mmc_switch);
>
> +int mmc_send_tuning(struct mmc_card *card, u32 opcode)
> +{
> + struct mmc_request mrq = {NULL};
> + struct mmc_command cmd = {0};
> + struct mmc_data data = {0};
> + struct scatterlist sg;
> + struct mmc_host *mmc = card->host;
> + struct mmc_ios *ios = &mmc->ios;
> + const u8 *tuning_block_pattern;
> + int size, err = 0;
> + u8 *data_buf;
> +
> + if (opcode == MMC_SEND_TUNING_BLOCK_HS200) {
I don't think we need to care about the opcode. Let's just check the bus_width.
> + if (ios->bus_width == MMC_BUS_WIDTH_8) {
> + tuning_block_pattern = tuning_blk_pattern_8bit;
> + size = sizeof(tuning_blk_pattern_8bit);
> + } else if (ios->bus_width == MMC_BUS_WIDTH_4) {
> + tuning_block_pattern = tuning_blk_pattern_4bit;
> + size = sizeof(tuning_blk_pattern_4bit);
> + } else
> + return -EINVAL;
> + } else if (opcode == MMC_SEND_TUNING_BLOCK) {
> + tuning_block_pattern = tuning_blk_pattern_4bit;
> + size = sizeof(tuning_blk_pattern_4bit);
> + } else
> + return -EINVAL;
> +
> + data_buf = kmalloc(size, GFP_KERNEL);
You should use kzalloc() to get the zeroed buffer you want.
> + if (!data_buf)
> + return -ENOMEM;
> +
> + mrq.cmd = &cmd;
> + mrq.data = &data;
> +
> + cmd.opcode = opcode;
> + cmd.flags = MMC_RSP_R1 | MMC_CMD_ADTC;
> +
> + data.blksz = size;
> + data.blocks = 1;
> + data.flags = MMC_DATA_READ;
These needs to be assigned as well:
data.sg = &sg;
data.sg_len = 1;
> +
> + mmc_set_data_timeout(&data, card);
mmc_set_data_timeout() doesn't handle CMD21/19.
The specs tells us about 40 commands should be executed within 150ms.
I would pick a value of 150ms, just to be sure we are inside that
range. Also, assign "data->timeout_ns" here, instead of relying on
mmc_set_data_timeout().
> + sg_init_one(&sg, data_buf, size);
> + memset(data_buf, 0, size);
> + mmc_wait_for_req(mmc, &mrq);
> +
> + if (cmd.error) {
> + err = cmd.error;
> + goto out;
> + }
> +
> + if (data.error) {
> + err = data.error;
> + goto out;
> + }
> +
> + if (memcmp(data_buf, tuning_block_pattern, size))
> + err = -EIO;
> +
> +out:
> + kfree(data_buf);
> + return err;
> +}
> +EXPORT_SYMBOL_GPL(mmc_send_tuning);
> +
> static int
> mmc_send_bus_test(struct mmc_card *card, struct mmc_host *host, u8 opcode,
> u8 len)
> diff --git a/include/linux/mmc/core.h b/include/linux/mmc/core.h
> index f206e29..82a0119 100644
> --- a/include/linux/mmc/core.h
> +++ b/include/linux/mmc/core.h
> @@ -154,6 +154,7 @@ extern void mmc_start_bkops(struct mmc_card *card, bool from_exception);
> extern int __mmc_switch(struct mmc_card *, u8, u8, u8, unsigned int, bool,
> bool, bool);
> extern int mmc_switch(struct mmc_card *, u8, u8, u8, unsigned int);
> +extern int mmc_send_tuning(struct mmc_card *, u32);
> extern int mmc_send_ext_csd(struct mmc_card *card, u8 *ext_csd);
>
> #define MMC_ERASE_ARG 0x00000000
> --
> 2.1.1
>
Kind regards
Uffe
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