leandrof/u-boot
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

SPI: EXYNOS: Add FDT support to driver.

Browse Source 
This patch adds FDT support to the SPI driver.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Rajeshwari Shinde <rajeshwari.s@samsung.com>
Acked-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
This commit is contained in:
Rajeshwari Shinde 2012-12-26 20:03:23 +00:00 committed by Minkyu Kang
parent cb9b23cda9
commit 4d3acb9df3
1 changed files with 90 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

96
drivers/spi/exynos_spi.c
View File

@ -20,6 +20,7 @@
#include <common.h>
#include <malloc.h>
#include <spi.h>
#include <fdtdec.h>
#include <asm/arch/clk.h>
#include <asm/arch/clock.h>
#include <asm/arch/cpu.h>
@ -28,16 +29,20 @@
#include <asm/arch-exynos/spi.h>
#include <asm/io.h>
DECLARE_GLOBAL_DATA_PTR;
/* Information about each SPI controller */
struct spi_bus {
enum periph_id periph_id;
s32 frequency; /* Default clock frequency, -1 for none */
struct exynos_spi *regs;
int inited; /* 1 if this bus is ready for use */
int node;
};
/* A list of spi buses that we know about */
static struct spi_bus spi_bus[EXYNOS5_SPI_NUM_CONTROLLERS];
static unsigned int bus_count;
struct exynos_spi_slave {
struct spi_slave slave;
@ -50,7 +55,7 @@ struct exynos_spi_slave {
static struct spi_bus *spi_get_bus(unsigned dev_index)
{
if (dev_index < EXYNOS5_SPI_NUM_CONTROLLERS)
if (dev_index < bus_count)
return &spi_bus[dev_index];
debug("%s: invalid bus %d", __func__, dev_index);
@ -347,21 +352,100 @@ static inline struct exynos_spi *get_spi_base(int dev_index)
(dev_index - 3);
}
/*
* Read the SPI config from the device tree node.
*
* @param blob FDT blob to read from
* @param node Node offset to read from
* @param bus SPI bus structure to fill with information
* @return 0 if ok, or -FDT_ERR_NOTFOUND if something was missing
*/
static int spi_get_config(const void *blob, int node, struct spi_bus *bus)
{
bus->node = node;
bus->regs = (struct exynos_spi *)fdtdec_get_addr(blob, node, "reg");
bus->periph_id = pinmux_decode_periph_id(blob, node);
if (bus->periph_id == PERIPH_ID_NONE) {
debug("%s: Invalid peripheral ID %d\n", __func__,
bus->periph_id);
return -FDT_ERR_NOTFOUND;
}
/* Use 500KHz as a suitable default */
bus->frequency = fdtdec_get_int(blob, node, "spi-max-frequency",
500000);
return 0;
}
/*
* Process a list of nodes, adding them to our list of SPI ports.
*
* @param blob fdt blob
* @param node_list list of nodes to process (any <=0 are ignored)
* @param count number of nodes to process
* @param is_dvc 1 if these are DVC ports, 0 if standard I2C
* @return 0 if ok, -1 on error
*/
static int process_nodes(const void *blob, int node_list[], int count)
{
int i;
/* build the i2c_controllers[] for each controller */
for (i = 0; i < count; i++) {
int node = node_list[i];
struct spi_bus *bus;
if (node <= 0)
continue;
bus = &spi_bus[i];
if (spi_get_config(blob, node, bus)) {
printf("exynos spi_init: failed to decode bus %d\n",
i);
return -1;
}
debug("spi: controller bus %d at %p, periph_id %d\n",
i, bus->regs, bus->periph_id);
bus->inited = 1;
bus_count++;
}
return 0;
}
/* Sadly there is no error return from this function */
void spi_init(void)
{
int i;
int count;
#ifdef CONFIG_OF_CONTROL
int node_list[EXYNOS5_SPI_NUM_CONTROLLERS];
const void *blob = gd->fdt_blob;
count = fdtdec_find_aliases_for_id(blob, "spi",
COMPAT_SAMSUNG_EXYNOS_SPI, node_list,
EXYNOS5_SPI_NUM_CONTROLLERS);
if (process_nodes(blob, node_list, count))
return;
#else
struct spi_bus *bus;
for (i = 0; i < EXYNOS5_SPI_NUM_CONTROLLERS; i++) {
bus = &spi_bus[i];
bus->regs = get_spi_base(i);
bus->periph_id = PERIPH_ID_SPI0 + i;
for (count = 0; count < EXYNOS5_SPI_NUM_CONTROLLERS; count++) {
bus = &spi_bus[count];
bus->regs = get_spi_base(count);
bus->periph_id = PERIPH_ID_SPI0 + count;
/* Although Exynos5 supports upto 50Mhz speed,
* we are setting it to 10Mhz for safe side
*/
bus->frequency = 10000000;
bus->inited = 1;
bus->node = 0;
bus_count = EXYNOS5_SPI_NUM_CONTROLLERS;
}
#endif
}