[U-Boot] [PATCH v3 08/13] sf: Add flash_read_reg support

[Jagan Teki]

Generic function for all spi-flash register reads.

Signed-off-by: Jagan Teki <jteki at openedev.com>
---
Changes for v3:
	- none
Changes for v2:
	- none

 drivers/mtd/spi/sf.c          | 23 +++++++++++++++++++++++
 drivers/mtd/spi/sf_internal.h |  3 +++
 2 files changed, 26 insertions(+)

diff --git a/drivers/mtd/spi/sf.c b/drivers/mtd/spi/sf.c
index 664e860..cb36946 100644
--- a/drivers/mtd/spi/sf.c
+++ b/drivers/mtd/spi/sf.c
@@ -9,6 +9,7 @@
 
 #include <common.h>
 #include <spi.h>
+#include <spi_flash.h>
 
 static int spi_flash_read_write(struct spi_slave *spi,
 				const u8 *cmd, size_t cmd_len,
@@ -56,3 +57,25 @@ int spi_flash_cmd_write(struct spi_slave *spi, const u8 *cmd, size_t cmd_len,
 {
 	return spi_flash_read_write(spi, cmd, cmd_len, data, NULL, data_len);
 }
+
+int flash_read_reg(struct spi_flash *flash, u8 cmd, u8 *val, int len)
+{
+	struct spi_slave *spi = flash->spi;
+	int ret;
+
+	ret = spi_claim_bus(spi);
+	if (ret < 0) {
+		debug("SF: unable to claim SPI bus\n");
+		return ret;
+	}
+
+	ret = spi_flash_read_write(spi, &cmd, 1, NULL, val, len);
+	if (ret < 0) {
+		debug("SF: error %d reading register %x\n", ret, cmd);
+		return ret;
+	}
+
+	spi_release_bus(spi);
+
+	return ret;
+}
diff --git a/drivers/mtd/spi/sf_internal.h b/drivers/mtd/spi/sf_internal.h
index 8a3e5ec..14b8b55 100644
--- a/drivers/mtd/spi/sf_internal.h
+++ b/drivers/mtd/spi/sf_internal.h
@@ -156,6 +156,9 @@ int spi_flash_cmd(struct spi_slave *spi, u8 cmd, void *response, size_t len);
 int spi_flash_cmd_read(struct spi_slave *spi, const u8 *cmd,
 		size_t cmd_len, void *data, size_t data_len);
 
+/* Read flash register - common call for all flash register reads */
+int flash_read_reg(struct spi_flash *flash, u8 cmd, u8 *val, int len);
+
 /*
  * Send a multi-byte command to the device followed by (optional)
  * data. Used for programming the flash array, etc.
-- 
1.9.1