bb39b8d99a
Update our copies of the brcm2708 patches to the latest rpi-3.10-y rebased against linux-3.10.y stable (3.10.32). This should hopefully make it easier for us in the future to leverage the raspberry/rpi-* branches. Signed-off-by: Florian Fainelli <florian@openwrt.org> SVN-Revision: 39770
68 lines
1.8 KiB
Diff
68 lines
1.8 KiB
Diff
From 75c9b03f90ca974cb072d96f423884b773ca5425 Mon Sep 17 00:00:00 2001
|
|
From: notro <notro@tronnes.org>
|
|
Date: Sat, 26 Jan 2013 20:38:03 +0100
|
|
Subject: [PATCH 056/174] spi-bcm2708: add 9-bit support using LoSSI mode
|
|
|
|
---
|
|
drivers/spi/spi-bcm2708.c | 30 ++++++++++++++++++++++++++++--
|
|
1 file changed, 28 insertions(+), 2 deletions(-)
|
|
|
|
--- a/drivers/spi/spi-bcm2708.c
|
|
+++ b/drivers/spi/spi-bcm2708.c
|
|
@@ -146,10 +146,31 @@ static inline void bcm2708_rd_fifo(struc
|
|
static inline void bcm2708_wr_fifo(struct bcm2708_spi *bs, int len)
|
|
{
|
|
u8 byte;
|
|
+ u16 val;
|
|
|
|
if (len > bs->len)
|
|
len = bs->len;
|
|
|
|
+ if (unlikely(bcm2708_rd(bs, SPI_CS) & SPI_CS_LEN)) {
|
|
+ /* LoSSI mode */
|
|
+ if (unlikely(len % 2)) {
|
|
+ printk(KERN_ERR"bcm2708_wr_fifo: length must be even, skipping.\n");
|
|
+ bs->len = 0;
|
|
+ return;
|
|
+ }
|
|
+ while (len) {
|
|
+ if (bs->tx_buf) {
|
|
+ val = *(const u16 *)bs->tx_buf;
|
|
+ bs->tx_buf += 2;
|
|
+ } else
|
|
+ val = 0;
|
|
+ bcm2708_wr(bs, SPI_FIFO, val);
|
|
+ bs->len -= 2;
|
|
+ len -= 2;
|
|
+ }
|
|
+ return;
|
|
+ }
|
|
+
|
|
while (len--) {
|
|
byte = bs->tx_buf ? *bs->tx_buf++ : 0;
|
|
bcm2708_wr(bs, SPI_FIFO, byte);
|
|
@@ -234,8 +255,12 @@ static int bcm2708_setup_state(struct sp
|
|
switch (bpw) {
|
|
case 8:
|
|
break;
|
|
+ case 9:
|
|
+ /* Reading in LoSSI mode is a special case. See 'BCM2835 ARM Peripherals' datasheet */
|
|
+ cs |= SPI_CS_LEN;
|
|
+ break;
|
|
default:
|
|
- dev_dbg(dev, "setup: invalid bits_per_word %u (must be 8)\n",
|
|
+ dev_dbg(dev, "setup: invalid bits_per_word %u (must be 8 or 9)\n",
|
|
bpw);
|
|
return -EINVAL;
|
|
}
|
|
@@ -283,7 +308,8 @@ static int bcm2708_process_transfer(stru
|
|
ret = bcm2708_setup_state(spi->master, &spi->dev, &state,
|
|
xfer->speed_hz ? xfer->speed_hz : spi->max_speed_hz,
|
|
spi->chip_select, spi->mode,
|
|
- spi->bits_per_word);
|
|
+ xfer->bits_per_word ? xfer->bits_per_word :
|
|
+ spi->bits_per_word);
|
|
if (ret)
|
|
return ret;
|
|
|