--- /dev/null
+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));
--- /dev/null
+From 1e41dc0ee2f3807328db95e4f87ff1333245190f Mon Sep 17 00:00:00 2001
+From: Florian Fainelli <florian@openwrt.org>
+Date: Fri, 20 Apr 2012 15:37:34 +0200
+Subject: [PATCH] spi/bcm63xx: don't use the stopping state
+
+We do not need to use a flag to indicate if the master driver is stopping
+it is sufficient to perform spi master unregistering in the platform
+driver's remove function.
+
+Signed-off-by: Florian Fainelli <florian@openwrt.org>
+Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
+---
+ drivers/spi/spi-bcm63xx.c | 13 ++-----------
+ 1 file changed, 2 insertions(+), 11 deletions(-)
+
+--- a/drivers/spi/spi-bcm63xx.c
++++ b/drivers/spi/spi-bcm63xx.c
+@@ -39,8 +39,6 @@
+ #define DRV_VER "0.1.2"
+
+ struct bcm63xx_spi {
+- spinlock_t lock;
+- int stopping;
+ struct completion done;
+
+ void __iomem *regs;
+@@ -161,9 +159,6 @@ static int bcm63xx_spi_setup(struct spi_
+
+ bs = spi_master_get_devdata(spi->master);
+
+- if (bs->stopping)
+- return -ESHUTDOWN;
+-
+ if (!spi->bits_per_word)
+ spi->bits_per_word = 8;
+
+@@ -410,10 +405,8 @@ static int __devinit bcm63xx_spi_probe(s
+ 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));
+ bs->rx_io = (const u8 *)(bs->regs + bcm63xx_spireg(SPI_RX_DATA));
+- spin_lock_init(&bs->lock);
+
+ /* Initialize hardware */
+ clk_enable(bs->clk);
+@@ -447,18 +440,16 @@ static int __devexit bcm63xx_spi_remove(
+ struct spi_master *master = platform_get_drvdata(pdev);
+ struct bcm63xx_spi *bs = spi_master_get_devdata(master);
+
++ spi_unregister_master(master);
++
+ /* reset spi block */
+ bcm_spi_writeb(bs, 0, SPI_INT_MASK);
+- spin_lock(&bs->lock);
+- bs->stopping = 1;
+
+ /* HW shutdown */
+ clk_disable(bs->clk);
+ clk_put(bs->clk);
+
+- spin_unlock(&bs->lock);
+ platform_set_drvdata(pdev, 0);
+- spi_unregister_master(master);
+
+ return 0;
+ }
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