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-rw-r--r--drivers/spi/Kconfig1
-rw-r--r--drivers/spi/spi_mpc83xx.c411
2 files changed, 282 insertions, 130 deletions
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index fae9e8f3d092..66ec5d8808de 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -126,7 +126,6 @@ config SPI_MPC52xx_PSC
config SPI_MPC83xx
tristate "Freescale MPC83xx/QUICC Engine SPI controller"
depends on SPI_MASTER && (PPC_83xx || QUICC_ENGINE) && EXPERIMENTAL
- select SPI_BITBANG
help
This enables using the Freescale MPC83xx and QUICC Engine SPI
controllers in master mode.
diff --git a/drivers/spi/spi_mpc83xx.c b/drivers/spi/spi_mpc83xx.c
index 189f706b9e4b..6832da6f7109 100644
--- a/drivers/spi/spi_mpc83xx.c
+++ b/drivers/spi/spi_mpc83xx.c
@@ -49,6 +49,7 @@ struct mpc83xx_spi_reg {
#define SPMODE_LEN(x) ((x) << 20)
#define SPMODE_PM(x) ((x) << 16)
#define SPMODE_OP (1 << 14)
+#define SPMODE_CG(x) ((x) << 7)
/*
* Default for SPI Mode:
@@ -67,10 +68,6 @@ struct mpc83xx_spi_reg {
/* SPI Controller driver's private data. */
struct mpc83xx_spi {
- /* bitbang has to be first */
- struct spi_bitbang bitbang;
- struct completion done;
-
struct mpc83xx_spi_reg __iomem *base;
/* rx & tx bufs from the spi_transfer */
@@ -82,7 +79,7 @@ struct mpc83xx_spi {
u32(*get_tx) (struct mpc83xx_spi *);
unsigned int count;
- u32 irq;
+ int irq;
unsigned nsecs; /* (clock cycle time)/2 */
@@ -94,6 +91,25 @@ struct mpc83xx_spi {
void (*activate_cs) (u8 cs, u8 polarity);
void (*deactivate_cs) (u8 cs, u8 polarity);
+
+ u8 busy;
+
+ struct workqueue_struct *workqueue;
+ struct work_struct work;
+
+ struct list_head queue;
+ spinlock_t lock;
+
+ struct completion done;
+};
+
+struct spi_mpc83xx_cs {
+ /* functions to deal with different sized buffers */
+ void (*get_rx) (u32 rx_data, struct mpc83xx_spi *);
+ u32 (*get_tx) (struct mpc83xx_spi *);
+ u32 rx_shift; /* RX data reg shift when in qe mode */
+ u32 tx_shift; /* TX data reg shift when in qe mode */
+ u32 hw_mode; /* Holds HW mode register settings */
};
static inline void mpc83xx_spi_write_reg(__be32 __iomem * reg, u32 val)
@@ -137,6 +153,7 @@ static void mpc83xx_spi_chipselect(struct spi_device *spi, int value)
{
struct mpc83xx_spi *mpc83xx_spi;
u8 pol = spi->mode & SPI_CS_HIGH ? 1 : 0;
+ struct spi_mpc83xx_cs *cs = spi->controller_state;
mpc83xx_spi = spi_master_get_devdata(spi->master);
@@ -147,50 +164,26 @@ static void mpc83xx_spi_chipselect(struct spi_device *spi, int value)
if (value == BITBANG_CS_ACTIVE) {
u32 regval = mpc83xx_spi_read_reg(&mpc83xx_spi->base->mode);
- u32 len = spi->bits_per_word;
- u8 pm;
- if (len == 32)
- len = 0;
- else
- len = len - 1;
-
- /* mask out bits we are going to set */
- regval &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH
- | SPMODE_LEN(0xF) | SPMODE_DIV16
- | SPMODE_PM(0xF) | SPMODE_REV | SPMODE_LOOP);
-
- if (spi->mode & SPI_CPHA)
- regval |= SPMODE_CP_BEGIN_EDGECLK;
- if (spi->mode & SPI_CPOL)
- regval |= SPMODE_CI_INACTIVEHIGH;
- if (!(spi->mode & SPI_LSB_FIRST))
- regval |= SPMODE_REV;
- if (spi->mode & SPI_LOOP)
- regval |= SPMODE_LOOP;
-
- regval |= SPMODE_LEN(len);
-
- if ((mpc83xx_spi->spibrg / spi->max_speed_hz) >= 64) {
- pm = mpc83xx_spi->spibrg / (spi->max_speed_hz * 64) - 1;
- if (pm > 0x0f) {
- dev_err(&spi->dev, "Requested speed is too "
- "low: %d Hz. Will use %d Hz instead.\n",
- spi->max_speed_hz,
- mpc83xx_spi->spibrg / 1024);
- pm = 0x0f;
- }
- regval |= SPMODE_PM(pm) | SPMODE_DIV16;
- } else {
- pm = mpc83xx_spi->spibrg / (spi->max_speed_hz * 4);
- if (pm)
- pm--;
- regval |= SPMODE_PM(pm);
+ mpc83xx_spi->rx_shift = cs->rx_shift;
+ mpc83xx_spi->tx_shift = cs->tx_shift;
+ mpc83xx_spi->get_rx = cs->get_rx;
+ mpc83xx_spi->get_tx = cs->get_tx;
+
+ if (cs->hw_mode != regval) {
+ unsigned long flags;
+ void *tmp_ptr = &mpc83xx_spi->base->mode;
+
+ regval = cs->hw_mode;
+ /* Turn off IRQs locally to minimize time that
+ * SPI is disabled
+ */
+ local_irq_save(flags);
+ /* Turn off SPI unit prior changing mode */
+ mpc83xx_spi_write_reg(tmp_ptr, regval & ~SPMODE_ENABLE);
+ mpc83xx_spi_write_reg(tmp_ptr, regval);
+ local_irq_restore(flags);
}
-
- /* Turn off SPI unit prior changing mode */
- mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, 0);
- mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, regval);
if (mpc83xx_spi->activate_cs)
mpc83xx_spi->activate_cs(spi->chip_select, pol);
}
@@ -201,8 +194,9 @@ int mpc83xx_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
{
struct mpc83xx_spi *mpc83xx_spi;
u32 regval;
- u8 bits_per_word;
+ u8 bits_per_word, pm;
u32 hz;
+ struct spi_mpc83xx_cs *cs = spi->controller_state;
mpc83xx_spi = spi_master_get_devdata(spi->master);
@@ -223,61 +217,191 @@ int mpc83xx_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
|| ((bits_per_word > 16) && (bits_per_word != 32)))
return -EINVAL;
- mpc83xx_spi->rx_shift = 0;
- mpc83xx_spi->tx_shift = 0;
+ if (!hz)
+ hz = spi->max_speed_hz;
+
+ cs->rx_shift = 0;
+ cs->tx_shift = 0;
if (bits_per_word <= 8) {
- mpc83xx_spi->get_rx = mpc83xx_spi_rx_buf_u8;
- mpc83xx_spi->get_tx = mpc83xx_spi_tx_buf_u8;
+ cs->get_rx = mpc83xx_spi_rx_buf_u8;
+ cs->get_tx = mpc83xx_spi_tx_buf_u8;
if (mpc83xx_spi->qe_mode) {
- mpc83xx_spi->rx_shift = 16;
- mpc83xx_spi->tx_shift = 24;
+ cs->rx_shift = 16;
+ cs->tx_shift = 24;
}
} else if (bits_per_word <= 16) {
- mpc83xx_spi->get_rx = mpc83xx_spi_rx_buf_u16;
- mpc83xx_spi->get_tx = mpc83xx_spi_tx_buf_u16;
+ cs->get_rx = mpc83xx_spi_rx_buf_u16;
+ cs->get_tx = mpc83xx_spi_tx_buf_u16;
if (mpc83xx_spi->qe_mode) {
- mpc83xx_spi->rx_shift = 16;
- mpc83xx_spi->tx_shift = 16;
+ cs->rx_shift = 16;
+ cs->tx_shift = 16;
}
} else if (bits_per_word <= 32) {
- mpc83xx_spi->get_rx = mpc83xx_spi_rx_buf_u32;
- mpc83xx_spi->get_tx = mpc83xx_spi_tx_buf_u32;
+ cs->get_rx = mpc83xx_spi_rx_buf_u32;
+ cs->get_tx = mpc83xx_spi_tx_buf_u32;
} else
return -EINVAL;
if (mpc83xx_spi->qe_mode && spi->mode & SPI_LSB_FIRST) {
- mpc83xx_spi->tx_shift = 0;
+ cs->tx_shift = 0;
if (bits_per_word <= 8)
- mpc83xx_spi->rx_shift = 8;
+ cs->rx_shift = 8;
else
- mpc83xx_spi->rx_shift = 0;
+ cs->rx_shift = 0;
}
- /* nsecs = (clock period)/2 */
- if (!hz)
- hz = spi->max_speed_hz;
- mpc83xx_spi->nsecs = (1000000000 / 2) / hz;
- if (mpc83xx_spi->nsecs > MAX_UDELAY_MS * 1000)
- return -EINVAL;
+ mpc83xx_spi->rx_shift = cs->rx_shift;
+ mpc83xx_spi->tx_shift = cs->tx_shift;
+ mpc83xx_spi->get_rx = cs->get_rx;
+ mpc83xx_spi->get_tx = cs->get_tx;
if (bits_per_word == 32)
bits_per_word = 0;
else
bits_per_word = bits_per_word - 1;
- regval = mpc83xx_spi_read_reg(&mpc83xx_spi->base->mode);
-
/* mask out bits we are going to set */
- regval &= ~(SPMODE_LEN(0xF) | SPMODE_REV);
- regval |= SPMODE_LEN(bits_per_word);
- if (!(spi->mode & SPI_LSB_FIRST))
- regval |= SPMODE_REV;
+ cs->hw_mode &= ~(SPMODE_LEN(0xF) | SPMODE_DIV16
+ | SPMODE_PM(0xF));
+
+ cs->hw_mode |= SPMODE_LEN(bits_per_word);
+
+ if ((mpc83xx_spi->spibrg / hz) >= 64) {
+ pm = mpc83xx_spi->spibrg / (hz * 64) - 1;
+ if (pm > 0x0f) {
+ dev_err(&spi->dev, "Requested speed is too "
+ "low: %d Hz. Will use %d Hz instead.\n",
+ hz, mpc83xx_spi->spibrg / 1024);
+ pm = 0x0f;
+ }
+ cs->hw_mode |= SPMODE_PM(pm) | SPMODE_DIV16;
+ } else {
+ pm = mpc83xx_spi->spibrg / (hz * 4);
+ if (pm)
+ pm--;
+ cs->hw_mode |= SPMODE_PM(pm);
+ }
+ regval = mpc83xx_spi_read_reg(&mpc83xx_spi->base->mode);
+ if (cs->hw_mode != regval) {
+ unsigned long flags;
+ void *tmp_ptr = &mpc83xx_spi->base->mode;
+
+ regval = cs->hw_mode;
+ /* Turn off IRQs locally to minimize time
+ * that SPI is disabled
+ */
+ local_irq_save(flags);
+ /* Turn off SPI unit prior changing mode */
+ mpc83xx_spi_write_reg(tmp_ptr, regval & ~SPMODE_ENABLE);
+ mpc83xx_spi_write_reg(tmp_ptr, regval);
+ local_irq_restore(flags);
+ }
+ return 0;
+}
- /* Turn off SPI unit prior changing mode */
- mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, 0);
- mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, regval);
+static int mpc83xx_spi_bufs(struct spi_device *spi, struct spi_transfer *t)
+{
+ struct mpc83xx_spi *mpc83xx_spi;
+ u32 word, len, bits_per_word;
- return 0;
+ mpc83xx_spi = spi_master_get_devdata(spi->master);
+
+ mpc83xx_spi->tx = t->tx_buf;
+ mpc83xx_spi->rx = t->rx_buf;
+ bits_per_word = spi->bits_per_word;
+ if (t->bits_per_word)
+ bits_per_word = t->bits_per_word;
+ len = t->len;
+ if (bits_per_word > 8)
+ len /= 2;
+ if (bits_per_word > 16)
+ len /= 2;
+ mpc83xx_spi->count = len;
+ INIT_COMPLETION(mpc83xx_spi->done);
+
+ /* enable rx ints */
+ mpc83xx_spi_write_reg(&mpc83xx_spi->base->mask, SPIM_NE);
+
+ /* transmit word */
+ word = mpc83xx_spi->get_tx(mpc83xx_spi);
+ mpc83xx_spi_write_reg(&mpc83xx_spi->base->transmit, word);
+
+ wait_for_completion(&mpc83xx_spi->done);
+
+ /* disable rx ints */
+ mpc83xx_spi_write_reg(&mpc83xx_spi->base->mask, 0);
+
+ return mpc83xx_spi->count;
+}
+
+static void mpc83xx_spi_work(struct work_struct *work)
+{
+ struct mpc83xx_spi *mpc83xx_spi =
+ container_of(work, struct mpc83xx_spi, work);
+
+ spin_lock_irq(&mpc83xx_spi->lock);
+ mpc83xx_spi->busy = 1;
+ while (!list_empty(&mpc83xx_spi->queue)) {
+ struct spi_message *m;
+ struct spi_device *spi;
+ struct spi_transfer *t = NULL;
+ unsigned cs_change;
+ int status, nsecs = 50;
+
+ m = container_of(mpc83xx_spi->queue.next,
+ struct spi_message, queue);
+ list_del_init(&m->queue);
+ spin_unlock_irq(&mpc83xx_spi->lock);
+
+ spi = m->spi;
+ cs_change = 1;
+ status = 0;
+ list_for_each_entry(t, &m->transfers, transfer_list) {
+ if (t->bits_per_word || t->speed_hz) {
+ /* Don't allow changes if CS is active */
+ status = -EINVAL;
+
+ if (cs_change)
+ status = mpc83xx_spi_setup_transfer(spi, t);
+ if (status < 0)
+ break;
+ }
+
+ if (cs_change)
+ mpc83xx_spi_chipselect(spi, BITBANG_CS_ACTIVE);
+ cs_change = t->cs_change;
+ if (t->len)
+ status = mpc83xx_spi_bufs(spi, t);
+ if (status) {
+ status = -EMSGSIZE;
+ break;
+ }
+ m->actual_length += t->len;
+
+ if (t->delay_usecs)
+ udelay(t->delay_usecs);
+
+ if (cs_change) {
+ ndelay(nsecs);
+ mpc83xx_spi_chipselect(spi, BITBANG_CS_INACTIVE);
+ ndelay(nsecs);
+ }
+ }
+
+ m->status = status;
+ m->complete(m->context);
+
+ if (status || !cs_change) {
+ ndelay(nsecs);
+ mpc83xx_spi_chipselect(spi, BITBANG_CS_INACTIVE);
+ }
+
+ mpc83xx_spi_setup_transfer(spi, NULL);
+
+ spin_lock_irq(&mpc83xx_spi->lock);
+ }
+ mpc83xx_spi->busy = 0;
+ spin_unlock_irq(&mpc83xx_spi->lock);
}
/* the spi->mode bits understood by this driver: */
@@ -286,9 +410,10 @@ int mpc83xx_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
static int mpc83xx_spi_setup(struct spi_device *spi)
{
- struct spi_bitbang *bitbang;
struct mpc83xx_spi *mpc83xx_spi;
int retval;
+ u32 hw_mode;
+ struct spi_mpc83xx_cs *cs = spi->controller_state;
if (spi->mode & ~MODEBITS) {
dev_dbg(&spi->dev, "setup: unsupported mode bits %x\n",
@@ -299,63 +424,56 @@ static int mpc83xx_spi_setup(struct spi_device *spi)
if (!spi->max_speed_hz)
return -EINVAL;
- bitbang = spi_master_get_devdata(spi->master);
+ if (!cs) {
+ cs = kzalloc(sizeof *cs, GFP_KERNEL);
+ if (!cs)
+ return -ENOMEM;
+ spi->controller_state = cs;
+ }
mpc83xx_spi = spi_master_get_devdata(spi->master);
if (!spi->bits_per_word)
spi->bits_per_word = 8;
+ hw_mode = cs->hw_mode; /* Save orginal settings */
+ cs->hw_mode = mpc83xx_spi_read_reg(&mpc83xx_spi->base->mode);
+ /* mask out bits we are going to set */
+ cs->hw_mode &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH
+ | SPMODE_REV | SPMODE_LOOP);
+
+ if (spi->mode & SPI_CPHA)
+ cs->hw_mode |= SPMODE_CP_BEGIN_EDGECLK;
+ if (spi->mode & SPI_CPOL)
+ cs->hw_mode |= SPMODE_CI_INACTIVEHIGH;
+ if (!(spi->mode & SPI_LSB_FIRST))
+ cs->hw_mode |= SPMODE_REV;
+ if (spi->mode & SPI_LOOP)
+ cs->hw_mode |= SPMODE_LOOP;
+
retval = mpc83xx_spi_setup_transfer(spi, NULL);
- if (retval < 0)
+ if (retval < 0) {
+ cs->hw_mode = hw_mode; /* Restore settings */
return retval;
+ }
- dev_dbg(&spi->dev, "%s, mode %d, %u bits/w, %u nsec\n",
+ dev_dbg(&spi->dev, "%s, mode %d, %u bits/w, %u Hz\n",
__func__, spi->mode & (SPI_CPOL | SPI_CPHA),
- spi->bits_per_word, 2 * mpc83xx_spi->nsecs);
-
+ spi->bits_per_word, spi->max_speed_hz);
+#if 0 /* Don't think this is needed */
/* NOTE we _need_ to call chipselect() early, ideally with adapter
* setup, unless the hardware defaults cooperate to avoid confusion
* between normal (active low) and inverted chipselects.
*/
/* deselect chip (low or high) */
- spin_lock(&bitbang->lock);
- if (!bitbang->busy) {
- bitbang->chipselect(spi, BITBANG_CS_INACTIVE);
- ndelay(mpc83xx_spi->nsecs);
- }
- spin_unlock(&bitbang->lock);
-
+ spin_lock(&mpc83xx_spi->lock);
+ if (!mpc83xx_spi->busy)
+ mpc83xx_spi_chipselect(spi, BITBANG_CS_INACTIVE);
+ spin_unlock(&mpc83xx_spi->lock);
+#endif
return 0;
}
-static int mpc83xx_spi_bufs(struct spi_device *spi, struct spi_transfer *t)
-{
- struct mpc83xx_spi *mpc83xx_spi;
- u32 word;
-
- mpc83xx_spi = spi_master_get_devdata(spi->master);
-
- mpc83xx_spi->tx = t->tx_buf;
- mpc83xx_spi->rx = t->rx_buf;
- mpc83xx_spi->count = t->len;
- INIT_COMPLETION(mpc83xx_spi->done);
-
- /* enable rx ints */
- mpc83xx_spi_write_reg(&mpc83xx_spi->base->mask, SPIM_NE);
-
- /* transmit word */
- word = mpc83xx_spi->get_tx(mpc83xx_spi);
- mpc83xx_spi_write_reg(&mpc83xx_spi->base->transmit, word);
-
- wait_for_completion(&mpc83xx_spi->done);
-
- /* disable rx ints */
- mpc83xx_spi_write_reg(&mpc83xx_spi->base->mask, 0);
-
- return t->len - mpc83xx_spi->count;
-}
-
irqreturn_t mpc83xx_spi_irq(s32 irq, void *context_data)
{
struct mpc83xx_spi *mpc83xx_spi = context_data;
@@ -395,6 +513,28 @@ irqreturn_t mpc83xx_spi_irq(s32 irq, void *context_data)
return ret;
}
+static int mpc83xx_spi_transfer(struct spi_device *spi,
+ struct spi_message *m)
+{
+ struct mpc83xx_spi *mpc83xx_spi = spi_master_get_devdata(spi->master);
+ unsigned long flags;
+
+ m->actual_length = 0;
+ m->status = -EINPROGRESS;
+
+ spin_lock_irqsave(&mpc83xx_spi->lock, flags);
+ list_add_tail(&m->queue, &mpc83xx_spi->queue);
+ queue_work(mpc83xx_spi->workqueue, &mpc83xx_spi->work);
+ spin_unlock_irqrestore(&mpc83xx_spi->lock, flags);
+
+ return 0;
+}
+
+
+static void mpc83xx_spi_cleanup(struct spi_device *spi)
+{
+ kfree(spi->controller_state);
+}
static int __init mpc83xx_spi_probe(struct platform_device *dev)
{
@@ -426,11 +566,11 @@ static int __init mpc83xx_spi_probe(struct platform_device *dev)
ret = -ENODEV;
goto free_master;
}
+ master->setup = mpc83xx_spi_setup;
+ master->transfer = mpc83xx_spi_transfer;
+ master->cleanup = mpc83xx_spi_cleanup;
+
mpc83xx_spi = spi_master_get_devdata(master);
- mpc83xx_spi->bitbang.master = spi_master_get(master);
- mpc83xx_spi->bitbang.chipselect = mpc83xx_spi_chipselect;
- mpc83xx_spi->bitbang.setup_transfer = mpc83xx_spi_setup_transfer;
- mpc83xx_spi->bitbang.txrx_bufs = mpc83xx_spi_bufs;
mpc83xx_spi->activate_cs = pdata->activate_cs;
mpc83xx_spi->deactivate_cs = pdata->deactivate_cs;
mpc83xx_spi->qe_mode = pdata->qe_mode;
@@ -445,7 +585,6 @@ static int __init mpc83xx_spi_probe(struct platform_device *dev)
mpc83xx_spi->tx_shift = 24;
}
- mpc83xx_spi->bitbang.master->setup = mpc83xx_spi_setup;
init_completion(&mpc83xx_spi->done);
mpc83xx_spi->base = ioremap(r->start, r->end - r->start + 1);
@@ -483,11 +622,21 @@ static int __init mpc83xx_spi_probe(struct platform_device *dev)
regval |= SPMODE_OP;
mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, regval);
+ spin_lock_init(&mpc83xx_spi->lock);
+ init_completion(&mpc83xx_spi->done);
+ INIT_WORK(&mpc83xx_spi->work, mpc83xx_spi_work);
+ INIT_LIST_HEAD(&mpc83xx_spi->queue);
- ret = spi_bitbang_start(&mpc83xx_spi->bitbang);
-
- if (ret != 0)
+ mpc83xx_spi->workqueue = create_singlethread_workqueue(
+ master->dev.parent->bus_id);
+ if (mpc83xx_spi->workqueue == NULL) {
+ ret = -EBUSY;
goto free_irq;
+ }
+
+ ret = spi_register_master(master);
+ if (ret < 0)
+ goto unreg_master;
printk(KERN_INFO
"%s: MPC83xx SPI Controller driver at 0x%p (irq = %d)\n",
@@ -495,6 +644,8 @@ static int __init mpc83xx_spi_probe(struct platform_device *dev)
return ret;
+unreg_master:
+ destroy_workqueue(mpc83xx_spi->workqueue);
free_irq:
free_irq(mpc83xx_spi->irq, mpc83xx_spi);
unmap_io:
@@ -515,10 +666,12 @@ static int __exit mpc83xx_spi_remove(struct platform_device *dev)
master = platform_get_drvdata(dev);
mpc83xx_spi = spi_master_get_devdata(master);
- spi_bitbang_stop(&mpc83xx_spi->bitbang);
+ flush_workqueue(mpc83xx_spi->workqueue);
+ destroy_workqueue(mpc83xx_spi->workqueue);
+ spi_unregister_master(master);
+
free_irq(mpc83xx_spi->irq, mpc83xx_spi);
iounmap(mpc83xx_spi->base);
- spi_master_put(mpc83xx_spi->bitbang.master);
return 0;
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-21 18:53:36 +0100