mirror of
git://projects.qi-hardware.com/openwrt-xburst.git
synced 2024-12-18 13:19:42 +02:00
0ef855fc75
git-svn-id: svn://svn.openwrt.org/openwrt/trunk@32581 3c298f89-4303-0410-b956-a3cf2f4a3e73
290 lines
8.4 KiB
Diff
290 lines
8.4 KiB
Diff
From cde4384e1037c15e5dd04c68d19c75798b6281dd Mon Sep 17 00:00:00 2001
|
|
From: Florian Fainelli <florian@openwrt.org>
|
|
Date: Fri, 20 Apr 2012 15:37:33 +0200
|
|
Subject: [PATCH] spi/bcm63xx: convert to the pump message infrastructure
|
|
|
|
This patch converts the bcm63xx SPI driver to use the SPI infrastructure
|
|
pump message queue. Since we were previously sleeping in the SPI
|
|
driver's transfer() function (which is not allowed) this is now fixed as well.
|
|
|
|
To complete that conversion a certain number of changes have been made:
|
|
- the transfer len is split into multiple hardware transfers in case its
|
|
size is bigger than the hardware FIFO size
|
|
- the FIFO refill is no longer done in the interrupt context, which was a
|
|
bad idea leading to quick interrupt handler re-entrancy
|
|
|
|
Tested-by: Tanguy Bouzeloc <tanguy.bouzeloc@efixo.com>
|
|
Signed-off-by: Florian Fainelli <florian@openwrt.org>
|
|
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
|
|
---
|
|
drivers/spi/spi-bcm63xx.c | 149 +++++++++++++++++++++++++++------------------
|
|
1 file changed, 89 insertions(+), 60 deletions(-)
|
|
|
|
--- a/drivers/spi/spi-bcm63xx.c
|
|
+++ b/drivers/spi/spi-bcm63xx.c
|
|
@@ -1,7 +1,7 @@
|
|
/*
|
|
* Broadcom BCM63xx SPI controller support
|
|
*
|
|
- * Copyright (C) 2009-2011 Florian Fainelli <florian@openwrt.org>
|
|
+ * Copyright (C) 2009-2012 Florian Fainelli <florian@openwrt.org>
|
|
* Copyright (C) 2010 Tanguy Bouzeloc <tanguy.bouzeloc@efixo.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
@@ -30,6 +30,8 @@
|
|
#include <linux/spi/spi.h>
|
|
#include <linux/completion.h>
|
|
#include <linux/err.h>
|
|
+#include <linux/workqueue.h>
|
|
+#include <linux/pm_runtime.h>
|
|
|
|
#include <bcm63xx_dev_spi.h>
|
|
|
|
@@ -96,17 +98,12 @@ static const unsigned bcm63xx_spi_freq_t
|
|
{ 391000, SPI_CLK_0_391MHZ }
|
|
};
|
|
|
|
-static int bcm63xx_spi_setup_transfer(struct spi_device *spi,
|
|
- struct spi_transfer *t)
|
|
+static int bcm63xx_spi_check_transfer(struct spi_device *spi,
|
|
+ struct spi_transfer *t)
|
|
{
|
|
- struct bcm63xx_spi *bs = spi_master_get_devdata(spi->master);
|
|
u8 bits_per_word;
|
|
- u8 clk_cfg, reg;
|
|
- u32 hz;
|
|
- int i;
|
|
|
|
bits_per_word = (t) ? t->bits_per_word : spi->bits_per_word;
|
|
- hz = (t) ? t->speed_hz : spi->max_speed_hz;
|
|
if (bits_per_word != 8) {
|
|
dev_err(&spi->dev, "%s, unsupported bits_per_word=%d\n",
|
|
__func__, bits_per_word);
|
|
@@ -119,6 +116,19 @@ static int bcm63xx_spi_setup_transfer(st
|
|
return -EINVAL;
|
|
}
|
|
|
|
+ return 0;
|
|
+}
|
|
+
|
|
+static void bcm63xx_spi_setup_transfer(struct spi_device *spi,
|
|
+ struct spi_transfer *t)
|
|
+{
|
|
+ struct bcm63xx_spi *bs = spi_master_get_devdata(spi->master);
|
|
+ u32 hz;
|
|
+ u8 clk_cfg, reg;
|
|
+ int i;
|
|
+
|
|
+ hz = (t) ? t->speed_hz : spi->max_speed_hz;
|
|
+
|
|
/* Find the closest clock configuration */
|
|
for (i = 0; i < SPI_CLK_MASK; i++) {
|
|
if (hz >= bcm63xx_spi_freq_table[i][0]) {
|
|
@@ -139,8 +149,6 @@ static int bcm63xx_spi_setup_transfer(st
|
|
bcm_spi_writeb(bs, reg, SPI_CLK_CFG);
|
|
dev_dbg(&spi->dev, "Setting clock register to %02x (hz %d)\n",
|
|
clk_cfg, hz);
|
|
-
|
|
- return 0;
|
|
}
|
|
|
|
/* the spi->mode bits understood by this driver: */
|
|
@@ -165,7 +173,7 @@ static int bcm63xx_spi_setup(struct spi_
|
|
return -EINVAL;
|
|
}
|
|
|
|
- ret = bcm63xx_spi_setup_transfer(spi, NULL);
|
|
+ ret = bcm63xx_spi_check_transfer(spi, NULL);
|
|
if (ret < 0) {
|
|
dev_err(&spi->dev, "setup: unsupported mode bits %x\n",
|
|
spi->mode & ~MODEBITS);
|
|
@@ -190,28 +198,29 @@ static void bcm63xx_spi_fill_tx_fifo(str
|
|
bs->remaining_bytes -= size;
|
|
}
|
|
|
|
-static int bcm63xx_txrx_bufs(struct spi_device *spi, struct spi_transfer *t)
|
|
+static unsigned int bcm63xx_txrx_bufs(struct spi_device *spi,
|
|
+ struct spi_transfer *t)
|
|
{
|
|
struct bcm63xx_spi *bs = spi_master_get_devdata(spi->master);
|
|
u16 msg_ctl;
|
|
u16 cmd;
|
|
|
|
+ /* Disable the CMD_DONE interrupt */
|
|
+ bcm_spi_writeb(bs, 0, SPI_INT_MASK);
|
|
+
|
|
dev_dbg(&spi->dev, "txrx: tx %p, rx %p, len %d\n",
|
|
t->tx_buf, t->rx_buf, t->len);
|
|
|
|
/* Transmitter is inhibited */
|
|
bs->tx_ptr = t->tx_buf;
|
|
bs->rx_ptr = t->rx_buf;
|
|
- init_completion(&bs->done);
|
|
|
|
if (t->tx_buf) {
|
|
bs->remaining_bytes = t->len;
|
|
bcm63xx_spi_fill_tx_fifo(bs);
|
|
}
|
|
|
|
- /* Enable the command done interrupt which
|
|
- * we use to determine completion of a command */
|
|
- bcm_spi_writeb(bs, SPI_INTR_CMD_DONE, SPI_INT_MASK);
|
|
+ init_completion(&bs->done);
|
|
|
|
/* Fill in the Message control register */
|
|
msg_ctl = (t->len << SPI_BYTE_CNT_SHIFT);
|
|
@@ -230,33 +239,76 @@ static int bcm63xx_txrx_bufs(struct spi_
|
|
cmd |= (0 << SPI_CMD_PREPEND_BYTE_CNT_SHIFT);
|
|
cmd |= (spi->chip_select << SPI_CMD_DEVICE_ID_SHIFT);
|
|
bcm_spi_writew(bs, cmd, SPI_CMD);
|
|
- wait_for_completion(&bs->done);
|
|
|
|
- /* Disable the CMD_DONE interrupt */
|
|
- bcm_spi_writeb(bs, 0, SPI_INT_MASK);
|
|
+ /* Enable the CMD_DONE interrupt */
|
|
+ bcm_spi_writeb(bs, SPI_INTR_CMD_DONE, SPI_INT_MASK);
|
|
|
|
return t->len - bs->remaining_bytes;
|
|
}
|
|
|
|
-static int bcm63xx_transfer(struct spi_device *spi, struct spi_message *m)
|
|
+static int bcm63xx_spi_prepare_transfer(struct spi_master *master)
|
|
{
|
|
- struct bcm63xx_spi *bs = spi_master_get_devdata(spi->master);
|
|
- struct spi_transfer *t;
|
|
- int ret = 0;
|
|
+ struct bcm63xx_spi *bs = spi_master_get_devdata(master);
|
|
|
|
- if (unlikely(list_empty(&m->transfers)))
|
|
- return -EINVAL;
|
|
+ pm_runtime_get_sync(&bs->pdev->dev);
|
|
|
|
- if (bs->stopping)
|
|
- return -ESHUTDOWN;
|
|
+ return 0;
|
|
+}
|
|
+
|
|
+static int bcm63xx_spi_unprepare_transfer(struct spi_master *master)
|
|
+{
|
|
+ struct bcm63xx_spi *bs = spi_master_get_devdata(master);
|
|
+
|
|
+ pm_runtime_put(&bs->pdev->dev);
|
|
+
|
|
+ return 0;
|
|
+}
|
|
+
|
|
+static int bcm63xx_spi_transfer_one(struct spi_master *master,
|
|
+ struct spi_message *m)
|
|
+{
|
|
+ struct bcm63xx_spi *bs = spi_master_get_devdata(master);
|
|
+ struct spi_transfer *t;
|
|
+ struct spi_device *spi = m->spi;
|
|
+ int status = 0;
|
|
+ unsigned int timeout = 0;
|
|
|
|
list_for_each_entry(t, &m->transfers, transfer_list) {
|
|
- ret += bcm63xx_txrx_bufs(spi, t);
|
|
- }
|
|
+ unsigned int len = t->len;
|
|
+ u8 rx_tail;
|
|
|
|
- m->complete(m->context);
|
|
+ status = bcm63xx_spi_check_transfer(spi, t);
|
|
+ if (status < 0)
|
|
+ goto exit;
|
|
+
|
|
+ /* configure adapter for a new transfer */
|
|
+ bcm63xx_spi_setup_transfer(spi, t);
|
|
+
|
|
+ while (len) {
|
|
+ /* send the data */
|
|
+ len -= bcm63xx_txrx_bufs(spi, t);
|
|
+
|
|
+ timeout = wait_for_completion_timeout(&bs->done, HZ);
|
|
+ if (!timeout) {
|
|
+ status = -ETIMEDOUT;
|
|
+ goto exit;
|
|
+ }
|
|
+
|
|
+ /* read out all data */
|
|
+ rx_tail = bcm_spi_readb(bs, SPI_RX_TAIL);
|
|
+
|
|
+ /* Read out all the data */
|
|
+ if (rx_tail)
|
|
+ memcpy_fromio(bs->rx_ptr, bs->rx_io, rx_tail);
|
|
+ }
|
|
+
|
|
+ m->actual_length += t->len;
|
|
+ }
|
|
+exit:
|
|
+ m->status = status;
|
|
+ spi_finalize_current_message(master);
|
|
|
|
- return ret;
|
|
+ return 0;
|
|
}
|
|
|
|
/* This driver supports single master mode only. Hence
|
|
@@ -267,39 +319,15 @@ static irqreturn_t bcm63xx_spi_interrupt
|
|
struct spi_master *master = (struct spi_master *)dev_id;
|
|
struct bcm63xx_spi *bs = spi_master_get_devdata(master);
|
|
u8 intr;
|
|
- u16 cmd;
|
|
|
|
/* Read interupts and clear them immediately */
|
|
intr = bcm_spi_readb(bs, SPI_INT_STATUS);
|
|
bcm_spi_writeb(bs, SPI_INTR_CLEAR_ALL, SPI_INT_STATUS);
|
|
bcm_spi_writeb(bs, 0, SPI_INT_MASK);
|
|
|
|
- /* A tansfer completed */
|
|
- if (intr & SPI_INTR_CMD_DONE) {
|
|
- u8 rx_tail;
|
|
-
|
|
- rx_tail = bcm_spi_readb(bs, SPI_RX_TAIL);
|
|
-
|
|
- /* Read out all the data */
|
|
- if (rx_tail)
|
|
- memcpy_fromio(bs->rx_ptr, bs->rx_io, rx_tail);
|
|
-
|
|
- /* See if there is more data to send */
|
|
- if (bs->remaining_bytes > 0) {
|
|
- bcm63xx_spi_fill_tx_fifo(bs);
|
|
-
|
|
- /* Start the transfer */
|
|
- bcm_spi_writew(bs, SPI_HD_W << SPI_MSG_TYPE_SHIFT,
|
|
- SPI_MSG_CTL);
|
|
- cmd = bcm_spi_readw(bs, SPI_CMD);
|
|
- cmd |= SPI_CMD_START_IMMEDIATE;
|
|
- cmd |= (0 << SPI_CMD_PREPEND_BYTE_CNT_SHIFT);
|
|
- bcm_spi_writeb(bs, SPI_INTR_CMD_DONE, SPI_INT_MASK);
|
|
- bcm_spi_writew(bs, cmd, SPI_CMD);
|
|
- } else {
|
|
- complete(&bs->done);
|
|
- }
|
|
- }
|
|
+ /* A transfer completed */
|
|
+ if (intr & SPI_INTR_CMD_DONE)
|
|
+ complete(&bs->done);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
@@ -345,7 +373,6 @@ static int __devinit bcm63xx_spi_probe(s
|
|
}
|
|
|
|
bs = spi_master_get_devdata(master);
|
|
- init_completion(&bs->done);
|
|
|
|
platform_set_drvdata(pdev, master);
|
|
bs->pdev = pdev;
|
|
@@ -379,7 +406,9 @@ static int __devinit bcm63xx_spi_probe(s
|
|
master->bus_num = pdata->bus_num;
|
|
master->num_chipselect = pdata->num_chipselect;
|
|
master->setup = bcm63xx_spi_setup;
|
|
- master->transfer = bcm63xx_transfer;
|
|
+ master->prepare_transfer_hardware = bcm63xx_spi_prepare_transfer;
|
|
+ master->unprepare_transfer_hardware = bcm63xx_spi_unprepare_transfer;
|
|
+ master->transfer_one_message = bcm63xx_spi_transfer_one;
|
|
bs->speed_hz = pdata->speed_hz;
|
|
bs->stopping = 0;
|
|
bs->tx_io = (u8 *)(bs->regs + bcm63xx_spireg(SPI_MSG_DATA));
|