[U-Boot] [PATCH v2] cmd: sspi: Add an additional argument to set the bus frequency

[Philipp Tomsich <philipp.tomsich@theobroma-systems.com>]

The spi command is rather useful for board verification, bring-up and
software testing.  One use in our lab is the testing of the clock
code, which requires the ability to send data at different SPI clocks.

The changeset adds an additional (optional) positional argument to the
'spi' command that allows the selection of a SPI clock for
communication (the previous default of 1MHz is retained, if the
argument is omitted).

Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
---
 cmd/spi.c | 20 +++++++++++++-------
 1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/cmd/spi.c b/cmd/spi.c
index f16ef9a..1cd2ebc 100644
--- a/cmd/spi.c
+++ b/cmd/spi.c
@@ -30,6 +30,8 @@
 #   define CONFIG_DEFAULT_SPI_MODE	SPI_MODE_0
 #endif
 
+#define SSPI_DEFAULT_HZ  1000000
+
 /*
  * Values from last command.
  */
@@ -40,7 +42,7 @@ static int   		bitlen;
 static uchar 		dout[MAX_SPI_BYTES];
 static uchar 		din[MAX_SPI_BYTES];
 
-static int do_spi_xfer(int bus, int cs)
+static int do_spi_xfer(int bus, int cs, unsigned int hz)
 {
 	struct spi_slave *slave;
 	int ret = 0;
@@ -53,12 +55,12 @@ static int do_spi_xfer(int bus, int cs)
 	str = strdup(name);
 	if (!str)
 		return -ENOMEM;
-	ret = spi_get_bus_and_cs(bus, cs, 1000000, mode, "spi_generic_drv",
+	ret = spi_get_bus_and_cs(bus, cs, hz, mode, "spi_generic_drv",
 				 str, &dev, &slave);
 	if (ret)
 		return ret;
 #else
-	slave = spi_setup_slave(bus, cs, 1000000, mode);
+	slave = spi_setup_slave(bus, cs, hz, mode);
 	if (!slave) {
 		printf("Invalid device %d:%d\n", bus, cs);
 		return -EINVAL;
@@ -109,6 +111,7 @@ int do_spi (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 	char  *cp = 0;
 	uchar tmp;
 	int   j;
+	unsigned int hz = SSPI_DEFAULT_HZ;
 
 	/*
 	 * We use the last specified parameters, unless new ones are
@@ -149,6 +152,8 @@ int do_spi (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 					dout[j / 2] |= tmp;
 			}
 		}
+		if (argc >= 5)
+			hz = simple_strtoul(argv[4], NULL, 10);
 	}
 
 	if ((bitlen < 0) || (bitlen >  (MAX_SPI_BYTES * 8))) {
@@ -156,7 +161,7 @@ int do_spi (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 		return 1;
 	}
 
-	if (do_spi_xfer(bus, cs))
+	if (do_spi_xfer(bus, cs, hz))
 		return 1;
 
 	return 0;
@@ -165,12 +170,13 @@ int do_spi (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 /***************************************************/
 
 U_BOOT_CMD(
-	sspi,	5,	1,	do_spi,
+	sspi,	6,	1,	do_spi,
 	"SPI utility command",
-	"[<bus>:]<cs>[.<mode>] <bit_len> <dout> - Send and receive bits\n"
+	"[<bus>:]<cs>[.<mode>] <bit_len> <dout> [<hz>] - Send and receive bits\n"
 	"<bus>     - Identifies the SPI bus\n"
 	"<cs>      - Identifies the chip select\n"
 	"<mode>    - Identifies the SPI mode to use\n"
 	"<bit_len> - Number of bits to send (base 10)\n"
-	"<dout>    - Hexadecimal string that gets sent"
+	"<dout>    - Hexadecimal string that gets sent\n"
+	"[<clk>]   - Bus clock in Hz (defaults to 1 MHz)"
 );
-- 
1.9.1