mmc: core: add core-level function for sending tuning commands

According to the SD card spec, Add a manual tuning command function
for SDR104/HS200.
Sending command 19 or command 21 to read data and compare with the
tunning 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@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

1 files changed, 70 insertions, 0 deletions

diff --git a/drivers/mmc/core/mmc_ops.c b/drivers/mmc/core/mmc_ops.c
index 23aa3a380f27..12b2a32df346 100644
--- a/drivers/mmc/core/mmc_ops.c
+++ b/drivers/mmc/core/mmc_ops.c
@@ -547,6 +547,76 @@ 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)
+{
+        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;
+        u32 opcode;
+
+        if (ios->bus_width == MMC_BUS_WIDTH_8) {
+                tuning_block_pattern = tuning_blk_pattern_8bit;
+                size = sizeof(tuning_blk_pattern_8bit);
+                opcode = MMC_SEND_TUNING_BLOCK_HS200;
+        } else if (ios->bus_width == MMC_BUS_WIDTH_4) {
+                tuning_block_pattern = tuning_blk_pattern_4bit;
+                size = sizeof(tuning_blk_pattern_4bit);
+                opcode = MMC_SEND_TUNING_BLOCK;
+        } else
+                return -EINVAL;
+
+        data_buf = kzalloc(size, GFP_KERNEL);
+        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;
+
+        /*
+         * According to the tuning specs, Tuning process
+         * is normally shorter 40 executions of CMD19,
+         * and timeout value should be shorter than 150 ms
+         */
+        data.timeout_ns = 150 * NSEC_PER_MSEC;
+
+        data.sg = &sg;
+        data.sg_len = 1;
+        sg_init_one(&sg, data_buf, 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)