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Diffstat (limited to 'drivers/spi/spi-atmel.c')
-rw-r--r--drivers/spi/spi-atmel.c106
1 files changed, 72 insertions, 34 deletions
diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index 656d137db25..ab2ed75d42f 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -22,9 +22,8 @@
#include <linux/platform_data/atmel.h>
#include <linux/of.h>
-#include <asm/io.h>
-#include <asm/gpio.h>
-#include <mach/cpu.h>
+#include <linux/io.h>
+#include <linux/gpio.h>
/* SPI register offsets */
#define SPI_CR 0x0000
@@ -39,6 +38,7 @@
#define SPI_CSR1 0x0034
#define SPI_CSR2 0x0038
#define SPI_CSR3 0x003c
+#define SPI_VERSION 0x00fc
#define SPI_RPR 0x0100
#define SPI_RCR 0x0104
#define SPI_TPR 0x0108
@@ -71,6 +71,8 @@
#define SPI_FDIV_SIZE 1
#define SPI_MODFDIS_OFFSET 4
#define SPI_MODFDIS_SIZE 1
+#define SPI_WDRBT_OFFSET 5
+#define SPI_WDRBT_SIZE 1
#define SPI_LLB_OFFSET 7
#define SPI_LLB_SIZE 1
#define SPI_PCS_OFFSET 16
@@ -180,6 +182,11 @@
#define spi_writel(port,reg,value) \
__raw_writel((value), (port)->regs + SPI_##reg)
+struct atmel_spi_caps {
+ bool is_spi2;
+ bool has_wdrbt;
+ bool has_dma_support;
+};
/*
* The core SPI transfer engine just talks to a register bank to set up
@@ -201,9 +208,12 @@ struct atmel_spi {
unsigned long current_remaining_bytes;
struct spi_transfer *next_transfer;
unsigned long next_remaining_bytes;
+ int done_status;
void *buffer;
dma_addr_t buffer_dma;
+
+ struct atmel_spi_caps caps;
};
/* Controller-specific per-slave state */
@@ -222,14 +232,10 @@ struct atmel_spi_device {
* - SPI_SR.TXEMPTY, SPI_SR.NSSR (and corresponding irqs)
* - SPI_CSRx.CSAAT
* - SPI_CSRx.SBCR allows faster clocking
- *
- * We can determine the controller version by reading the VERSION
- * register, but I haven't checked that it exists on all chips, and
- * this is cheaper anyway.
*/
-static bool atmel_spi_is_v2(void)
+static bool atmel_spi_is_v2(struct atmel_spi *as)
{
- return !cpu_is_at91rm9200();
+ return as->caps.is_spi2;
}
/*
@@ -250,11 +256,6 @@ static bool atmel_spi_is_v2(void)
* Master on Chip Select 0.") No workaround exists for that ... so for
* nCS0 on that chip, we (a) don't use the GPIO, (b) can't support CS_HIGH,
* and (c) will trigger that first erratum in some cases.
- *
- * TODO: Test if the atmel_spi_is_v2() branch below works on
- * AT91RM9200 if we use some other register than CSR0. However, don't
- * do this unconditionally since AP7000 has an errata where the BITS
- * field in CSR0 overrides all other CSRs.
*/
static void cs_activate(struct atmel_spi *as, struct spi_device *spi)
@@ -263,15 +264,24 @@ static void cs_activate(struct atmel_spi *as, struct spi_device *spi)
unsigned active = spi->mode & SPI_CS_HIGH;
u32 mr;
- if (atmel_spi_is_v2()) {
- /*
- * Always use CSR0. This ensures that the clock
- * switches to the correct idle polarity before we
- * toggle the CS.
+ if (atmel_spi_is_v2(as)) {
+ spi_writel(as, CSR0 + 4 * spi->chip_select, asd->csr);
+ /* For the low SPI version, there is a issue that PDC transfer
+ * on CS1,2,3 needs SPI_CSR0.BITS config as SPI_CSR1,2,3.BITS
*/
spi_writel(as, CSR0, asd->csr);
- spi_writel(as, MR, SPI_BF(PCS, 0x0e) | SPI_BIT(MODFDIS)
- | SPI_BIT(MSTR));
+ if (as->caps.has_wdrbt) {
+ spi_writel(as, MR,
+ SPI_BF(PCS, ~(0x01 << spi->chip_select))
+ | SPI_BIT(WDRBT)
+ | SPI_BIT(MODFDIS)
+ | SPI_BIT(MSTR));
+ } else {
+ spi_writel(as, MR,
+ SPI_BF(PCS, ~(0x01 << spi->chip_select))
+ | SPI_BIT(MODFDIS)
+ | SPI_BIT(MSTR));
+ }
mr = spi_readl(as, MR);
gpio_set_value(asd->npcs_pin, active);
} else {
@@ -318,7 +328,7 @@ static void cs_deactivate(struct atmel_spi *as, struct spi_device *spi)
asd->npcs_pin, active ? " (low)" : "",
mr);
- if (atmel_spi_is_v2() || spi->chip_select != 0)
+ if (atmel_spi_is_v2(as) || spi->chip_select != 0)
gpio_set_value(asd->npcs_pin, !active);
}
@@ -544,15 +554,15 @@ static void atmel_spi_dma_unmap_xfer(struct spi_master *master,
static void
atmel_spi_msg_done(struct spi_master *master, struct atmel_spi *as,
- struct spi_message *msg, int status, int stay)
+ struct spi_message *msg, int stay)
{
- if (!stay || status < 0)
+ if (!stay || as->done_status < 0)
cs_deactivate(as, msg->spi);
else
as->stay = msg->spi;
list_del(&msg->queue);
- msg->status = status;
+ msg->status = as->done_status;
dev_dbg(master->dev.parent,
"xfer complete: %u bytes transferred\n",
@@ -564,6 +574,7 @@ atmel_spi_msg_done(struct spi_master *master, struct atmel_spi *as,
as->current_transfer = NULL;
as->next_transfer = NULL;
+ as->done_status = 0;
/* continue if needed */
if (list_empty(&as->queue) || as->stopping)
@@ -641,7 +652,8 @@ atmel_spi_interrupt(int irq, void *dev_id)
/* Clear any overrun happening while cleaning up */
spi_readl(as, SR);
- atmel_spi_msg_done(master, as, msg, -EIO, 0);
+ as->done_status = -EIO;
+ atmel_spi_msg_done(master, as, msg, 0);
} else if (pending & (SPI_BIT(RXBUFF) | SPI_BIT(ENDRX))) {
ret = IRQ_HANDLED;
@@ -659,7 +671,7 @@ atmel_spi_interrupt(int irq, void *dev_id)
if (atmel_spi_xfer_is_last(msg, xfer)) {
/* report completed message */
- atmel_spi_msg_done(master, as, msg, 0,
+ atmel_spi_msg_done(master, as, msg,
xfer->cs_change);
} else {
if (xfer->cs_change) {
@@ -719,7 +731,7 @@ static int atmel_spi_setup(struct spi_device *spi)
}
/* see notes above re chipselect */
- if (!atmel_spi_is_v2()
+ if (!atmel_spi_is_v2(as)
&& spi->chip_select == 0
&& (spi->mode & SPI_CS_HIGH)) {
dev_dbg(&spi->dev, "setup: can't be active-high\n");
@@ -728,7 +740,7 @@ static int atmel_spi_setup(struct spi_device *spi)
/* v1 chips start out at half the peripheral bus speed. */
bus_hz = clk_get_rate(as->clk);
- if (!atmel_spi_is_v2())
+ if (!atmel_spi_is_v2(as))
bus_hz /= 2;
if (spi->max_speed_hz) {
@@ -804,7 +816,7 @@ static int atmel_spi_setup(struct spi_device *spi)
"setup: %lu Hz bpw %u mode 0x%x -> csr%d %08x\n",
bus_hz / scbr, bits, spi->mode, spi->chip_select, csr);
- if (!atmel_spi_is_v2())
+ if (!atmel_spi_is_v2(as))
spi_writel(as, CSR0 + 4 * spi->chip_select, csr);
return 0;
@@ -910,6 +922,23 @@ static void atmel_spi_cleanup(struct spi_device *spi)
kfree(asd);
}
+static inline unsigned int atmel_get_version(struct atmel_spi *as)
+{
+ return spi_readl(as, VERSION) & 0x00000fff;
+}
+
+static void atmel_get_caps(struct atmel_spi *as)
+{
+ unsigned int version;
+
+ version = atmel_get_version(as);
+ dev_info(&as->pdev->dev, "version: 0x%x\n", version);
+
+ as->caps.is_spi2 = version > 0x121;
+ as->caps.has_wdrbt = version >= 0x210;
+ as->caps.has_dma_support = version >= 0x212;
+}
+
/*-------------------------------------------------------------------------*/
static int atmel_spi_probe(struct platform_device *pdev)
@@ -970,6 +999,8 @@ static int atmel_spi_probe(struct platform_device *pdev)
as->irq = irq;
as->clk = clk;
+ atmel_get_caps(as);
+
ret = request_irq(irq, atmel_spi_interrupt, 0,
dev_name(&pdev->dev), master);
if (ret)
@@ -979,7 +1010,12 @@ static int atmel_spi_probe(struct platform_device *pdev)
clk_enable(clk);
spi_writel(as, CR, SPI_BIT(SWRST));
spi_writel(as, CR, SPI_BIT(SWRST)); /* AT91SAM9263 Rev B workaround */
- spi_writel(as, MR, SPI_BIT(MSTR) | SPI_BIT(MODFDIS));
+ if (as->caps.has_wdrbt) {
+ spi_writel(as, MR, SPI_BIT(WDRBT) | SPI_BIT(MODFDIS)
+ | SPI_BIT(MSTR));
+ } else {
+ spi_writel(as, MR, SPI_BIT(MSTR) | SPI_BIT(MODFDIS));
+ }
spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS));
spi_writel(as, CR, SPI_BIT(SPIEN));
@@ -1014,6 +1050,7 @@ static int atmel_spi_remove(struct platform_device *pdev)
struct spi_master *master = platform_get_drvdata(pdev);
struct atmel_spi *as = spi_master_get_devdata(master);
struct spi_message *msg;
+ struct spi_transfer *xfer;
/* reset the hardware and block queue progress */
spin_lock_irq(&as->lock);
@@ -1025,9 +1062,10 @@ static int atmel_spi_remove(struct platform_device *pdev)
/* Terminate remaining queued transfers */
list_for_each_entry(msg, &as->queue, queue) {
- /* REVISIT unmapping the dma is a NOP on ARM and AVR32
- * but we shouldn't depend on that...
- */
+ list_for_each_entry(xfer, &msg->transfers, transfer_list) {
+ if (!msg->is_dma_mapped)
+ atmel_spi_dma_unmap_xfer(master, xfer);
+ }
msg->status = -ESHUTDOWN;
msg->complete(msg->context);
}