#define RESET_DMA_CHANNEL (DCSR_NODESC | DMA_INT_MASK)
#define IS_DMA_ALIGNED(x) (((u32)(x)&0x07)==0)
+/* for testing SSCR1 changes that require SSP restart, basically
+ * everything except the service and interrupt enables */
+#define SSCR1_CHANGE_MASK (SSCR1_TTELP | SSCR1_TTE | SSCR1_EBCEI | SSCR1_SCFR \
+ | SSCR1_ECRA | SSCR1_ECRB | SSCR1_SCLKDIR \
+ | SSCR1_RWOT | SSCR1_TRAIL | SSCR1_PINTE \
+ | SSCR1_STRF | SSCR1_EFWR |SSCR1_RFT \
+ | SSCR1_TFT | SSCR1_SPH | SSCR1_SPO | SSCR1_LBM)
+
#define DEFINE_SSP_REG(reg, off) \
static inline u32 read_##reg(void *p) { return __raw_readl(p + (off)); } \
static inline void write_##reg(u32 v, void *p) { __raw_writel(v, p + (off)); }
u8 n_bytes;
u32 dma_width;
int cs_change;
- void (*write)(struct driver_data *drv_data);
- void (*read)(struct driver_data *drv_data);
+ int (*write)(struct driver_data *drv_data);
+ int (*read)(struct driver_data *drv_data);
irqreturn_t (*transfer_handler)(struct driver_data *drv_data);
void (*cs_control)(u32 command);
};
struct chip_data {
u32 cr0;
u32 cr1;
- u32 to;
u32 psp;
u32 timeout;
u8 n_bytes;
u8 enable_dma;
u8 bits_per_word;
u32 speed_hz;
- void (*write)(struct driver_data *drv_data);
- void (*read)(struct driver_data *drv_data);
+ int (*write)(struct driver_data *drv_data);
+ int (*read)(struct driver_data *drv_data);
void (*cs_control)(u32 command);
};
-static void pump_messages(void *data);
+static void pump_messages(struct work_struct *work);
static int flush(struct driver_data *drv_data)
{
return limit;
}
-static void restore_state(struct driver_data *drv_data)
-{
- void *reg = drv_data->ioaddr;
-
- /* Clear status and disable clock */
- write_SSSR(drv_data->clear_sr, reg);
- write_SSCR0(drv_data->cur_chip->cr0 & ~SSCR0_SSE, reg);
-
- /* Load the registers */
- write_SSCR1(drv_data->cur_chip->cr1, reg);
- write_SSCR0(drv_data->cur_chip->cr0, reg);
- if (drv_data->ssp_type != PXA25x_SSP) {
- write_SSTO(0, reg);
- write_SSPSP(drv_data->cur_chip->psp, reg);
- }
-}
-
static void null_cs_control(u32 command)
{
}
-static void null_writer(struct driver_data *drv_data)
+static int null_writer(struct driver_data *drv_data)
{
void *reg = drv_data->ioaddr;
u8 n_bytes = drv_data->n_bytes;
- while ((read_SSSR(reg) & SSSR_TNF)
- && (drv_data->tx < drv_data->tx_end)) {
- write_SSDR(0, reg);
- drv_data->tx += n_bytes;
- }
+ if (((read_SSSR(reg) & 0x00000f00) == 0x00000f00)
+ || (drv_data->tx == drv_data->tx_end))
+ return 0;
+
+ write_SSDR(0, reg);
+ drv_data->tx += n_bytes;
+
+ return 1;
}
-static void null_reader(struct driver_data *drv_data)
+static int null_reader(struct driver_data *drv_data)
{
void *reg = drv_data->ioaddr;
u8 n_bytes = drv_data->n_bytes;
while ((read_SSSR(reg) & SSSR_RNE)
- && (drv_data->rx < drv_data->rx_end)) {
+ && (drv_data->rx < drv_data->rx_end)) {
read_SSDR(reg);
drv_data->rx += n_bytes;
}
+
+ return drv_data->rx == drv_data->rx_end;
}
-static void u8_writer(struct driver_data *drv_data)
+static int u8_writer(struct driver_data *drv_data)
{
void *reg = drv_data->ioaddr;
- while ((read_SSSR(reg) & SSSR_TNF)
- && (drv_data->tx < drv_data->tx_end)) {
- write_SSDR(*(u8 *)(drv_data->tx), reg);
- ++drv_data->tx;
- }
+ if (((read_SSSR(reg) & 0x00000f00) == 0x00000f00)
+ || (drv_data->tx == drv_data->tx_end))
+ return 0;
+
+ write_SSDR(*(u8 *)(drv_data->tx), reg);
+ ++drv_data->tx;
+
+ return 1;
}
-static void u8_reader(struct driver_data *drv_data)
+static int u8_reader(struct driver_data *drv_data)
{
void *reg = drv_data->ioaddr;
while ((read_SSSR(reg) & SSSR_RNE)
- && (drv_data->rx < drv_data->rx_end)) {
+ && (drv_data->rx < drv_data->rx_end)) {
*(u8 *)(drv_data->rx) = read_SSDR(reg);
++drv_data->rx;
}
+
+ return drv_data->rx == drv_data->rx_end;
}
-static void u16_writer(struct driver_data *drv_data)
+static int u16_writer(struct driver_data *drv_data)
{
void *reg = drv_data->ioaddr;
- while ((read_SSSR(reg) & SSSR_TNF)
- && (drv_data->tx < drv_data->tx_end)) {
- write_SSDR(*(u16 *)(drv_data->tx), reg);
- drv_data->tx += 2;
- }
+ if (((read_SSSR(reg) & 0x00000f00) == 0x00000f00)
+ || (drv_data->tx == drv_data->tx_end))
+ return 0;
+
+ write_SSDR(*(u16 *)(drv_data->tx), reg);
+ drv_data->tx += 2;
+
+ return 1;
}
-static void u16_reader(struct driver_data *drv_data)
+static int u16_reader(struct driver_data *drv_data)
{
void *reg = drv_data->ioaddr;
while ((read_SSSR(reg) & SSSR_RNE)
- && (drv_data->rx < drv_data->rx_end)) {
+ && (drv_data->rx < drv_data->rx_end)) {
*(u16 *)(drv_data->rx) = read_SSDR(reg);
drv_data->rx += 2;
}
+
+ return drv_data->rx == drv_data->rx_end;
}
-static void u32_writer(struct driver_data *drv_data)
+
+static int u32_writer(struct driver_data *drv_data)
{
void *reg = drv_data->ioaddr;
- while ((read_SSSR(reg) & SSSR_TNF)
- && (drv_data->tx < drv_data->tx_end)) {
- write_SSDR(*(u32 *)(drv_data->tx), reg);
- drv_data->tx += 4;
- }
+ if (((read_SSSR(reg) & 0x00000f00) == 0x00000f00)
+ || (drv_data->tx == drv_data->tx_end))
+ return 0;
+
+ write_SSDR(*(u32 *)(drv_data->tx), reg);
+ drv_data->tx += 4;
+
+ return 1;
}
-static void u32_reader(struct driver_data *drv_data)
+static int u32_reader(struct driver_data *drv_data)
{
void *reg = drv_data->ioaddr;
while ((read_SSSR(reg) & SSSR_RNE)
- && (drv_data->rx < drv_data->rx_end)) {
+ && (drv_data->rx < drv_data->rx_end)) {
*(u32 *)(drv_data->rx) = read_SSDR(reg);
drv_data->rx += 4;
}
+
+ return drv_data->rx == drv_data->rx_end;
}
static void *next_transfer(struct driver_data *drv_data)
return limit;
}
-static void dma_handler(int channel, void *data, struct pt_regs *regs)
+void dma_error_stop(struct driver_data *drv_data, const char *msg)
{
- struct driver_data *drv_data = data;
- struct spi_message *msg = drv_data->cur_msg;
void *reg = drv_data->ioaddr;
- u32 irq_status = DCSR(channel) & DMA_INT_MASK;
- u32 trailing_sssr = 0;
- if (irq_status & DCSR_BUSERR) {
+ /* Stop and reset */
+ DCSR(drv_data->rx_channel) = RESET_DMA_CHANNEL;
+ DCSR(drv_data->tx_channel) = RESET_DMA_CHANNEL;
+ write_SSSR(drv_data->clear_sr, reg);
+ write_SSCR1(read_SSCR1(reg) & ~drv_data->dma_cr1, reg);
+ if (drv_data->ssp_type != PXA25x_SSP)
+ write_SSTO(0, reg);
+ flush(drv_data);
+ write_SSCR0(read_SSCR0(reg) & ~SSCR0_SSE, reg);
- /* Disable interrupts, clear status and reset DMA */
- write_SSCR0(read_SSCR0(reg) & ~SSCR0_SSE, reg);
- write_SSCR1(read_SSCR1(reg) & ~drv_data->dma_cr1, reg);
- if (drv_data->ssp_type != PXA25x_SSP)
- write_SSTO(0, reg);
- write_SSSR(drv_data->clear_sr, reg);
- DCSR(drv_data->rx_channel) = RESET_DMA_CHANNEL;
- DCSR(drv_data->tx_channel) = RESET_DMA_CHANNEL;
+ unmap_dma_buffers(drv_data);
- if (flush(drv_data) == 0)
- dev_err(&drv_data->pdev->dev,
- "dma_handler: flush fail\n");
+ dev_err(&drv_data->pdev->dev, "%s\n", msg);
+
+ drv_data->cur_msg->state = ERROR_STATE;
+ tasklet_schedule(&drv_data->pump_transfers);
+}
+
+static void dma_transfer_complete(struct driver_data *drv_data)
+{
+ void *reg = drv_data->ioaddr;
+ struct spi_message *msg = drv_data->cur_msg;
+
+ /* Clear and disable interrupts on SSP and DMA channels*/
+ write_SSCR1(read_SSCR1(reg) & ~drv_data->dma_cr1, reg);
+ write_SSSR(drv_data->clear_sr, reg);
+ DCSR(drv_data->tx_channel) = RESET_DMA_CHANNEL;
+ DCSR(drv_data->rx_channel) = RESET_DMA_CHANNEL;
+
+ if (wait_dma_channel_stop(drv_data->rx_channel) == 0)
+ dev_err(&drv_data->pdev->dev,
+ "dma_handler: dma rx channel stop failed\n");
+
+ if (wait_ssp_rx_stall(drv_data->ioaddr) == 0)
+ dev_err(&drv_data->pdev->dev,
+ "dma_transfer: ssp rx stall failed\n");
- unmap_dma_buffers(drv_data);
+ unmap_dma_buffers(drv_data);
+
+ /* update the buffer pointer for the amount completed in dma */
+ drv_data->rx += drv_data->len -
+ (DCMD(drv_data->rx_channel) & DCMD_LENGTH);
+
+ /* read trailing data from fifo, it does not matter how many
+ * bytes are in the fifo just read until buffer is full
+ * or fifo is empty, which ever occurs first */
+ drv_data->read(drv_data);
+
+ /* return count of what was actually read */
+ msg->actual_length += drv_data->len -
+ (drv_data->rx_end - drv_data->rx);
+
+ /* Release chip select if requested, transfer delays are
+ * handled in pump_transfers */
+ if (drv_data->cs_change)
+ drv_data->cs_control(PXA2XX_CS_DEASSERT);
+
+ /* Move to next transfer */
+ msg->state = next_transfer(drv_data);
+
+ /* Schedule transfer tasklet */
+ tasklet_schedule(&drv_data->pump_transfers);
+}
+
+static void dma_handler(int channel, void *data)
+{
+ struct driver_data *drv_data = data;
+ u32 irq_status = DCSR(channel) & DMA_INT_MASK;
+
+ if (irq_status & DCSR_BUSERR) {
if (channel == drv_data->tx_channel)
- dev_err(&drv_data->pdev->dev,
- "dma_handler: bad bus address on "
- "tx channel %d, source %x target = %x\n",
- channel, DSADR(channel), DTADR(channel));
+ dma_error_stop(drv_data,
+ "dma_handler: "
+ "bad bus address on tx channel");
else
- dev_err(&drv_data->pdev->dev,
- "dma_handler: bad bus address on "
- "rx channel %d, source %x target = %x\n",
- channel, DSADR(channel), DTADR(channel));
-
- msg->state = ERROR_STATE;
- tasklet_schedule(&drv_data->pump_transfers);
+ dma_error_stop(drv_data,
+ "dma_handler: "
+ "bad bus address on rx channel");
+ return;
}
/* PXA255x_SSP has no timeout interrupt, wait for tailing bytes */
- if ((drv_data->ssp_type == PXA25x_SSP)
- && (channel == drv_data->tx_channel)
- && (irq_status & DCSR_ENDINTR)) {
+ if ((channel == drv_data->tx_channel)
+ && (irq_status & DCSR_ENDINTR)
+ && (drv_data->ssp_type == PXA25x_SSP)) {
/* Wait for rx to stall */
if (wait_ssp_rx_stall(drv_data->ioaddr) == 0)
dev_err(&drv_data->pdev->dev,
"dma_handler: ssp rx stall failed\n");
- /* Clear and disable interrupts on SSP and DMA channels*/
- write_SSCR1(read_SSCR1(reg) & ~drv_data->dma_cr1, reg);
- write_SSSR(drv_data->clear_sr, reg);
- DCSR(drv_data->tx_channel) = RESET_DMA_CHANNEL;
- DCSR(drv_data->rx_channel) = RESET_DMA_CHANNEL;
- if (wait_dma_channel_stop(drv_data->rx_channel) == 0)
- dev_err(&drv_data->pdev->dev,
- "dma_handler: dma rx channel stop failed\n");
-
- unmap_dma_buffers(drv_data);
-
- /* Read trailing bytes */
- /* Calculate number of trailing bytes, read them */
- trailing_sssr = read_SSSR(reg);
- if ((trailing_sssr & 0xf008) != 0xf000) {
- drv_data->rx = drv_data->rx_end -
- (((trailing_sssr >> 12) & 0x0f) + 1);
- drv_data->read(drv_data);
- }
- msg->actual_length += drv_data->len;
-
- /* Release chip select if requested, transfer delays are
- * handled in pump_transfers */
- if (drv_data->cs_change)
- drv_data->cs_control(PXA2XX_CS_DEASSERT);
-
- /* Move to next transfer */
- msg->state = next_transfer(drv_data);
-
- /* Schedule transfer tasklet */
- tasklet_schedule(&drv_data->pump_transfers);
+ /* finish this transfer, start the next */
+ dma_transfer_complete(drv_data);
}
}
static irqreturn_t dma_transfer(struct driver_data *drv_data)
{
u32 irq_status;
- u32 trailing_sssr = 0;
- struct spi_message *msg = drv_data->cur_msg;
void *reg = drv_data->ioaddr;
irq_status = read_SSSR(reg) & drv_data->mask_sr;
if (irq_status & SSSR_ROR) {
- /* Clear and disable interrupts on SSP and DMA channels*/
- write_SSCR0(read_SSCR0(reg) & ~SSCR0_SSE, reg);
- write_SSCR1(read_SSCR1(reg) & ~drv_data->dma_cr1, reg);
- if (drv_data->ssp_type != PXA25x_SSP)
- write_SSTO(0, reg);
- write_SSSR(drv_data->clear_sr, reg);
- DCSR(drv_data->tx_channel) = RESET_DMA_CHANNEL;
- DCSR(drv_data->rx_channel) = RESET_DMA_CHANNEL;
- unmap_dma_buffers(drv_data);
-
- if (flush(drv_data) == 0)
- dev_err(&drv_data->pdev->dev,
- "dma_transfer: flush fail\n");
-
- dev_warn(&drv_data->pdev->dev, "dma_transfer: fifo overun\n");
-
- drv_data->cur_msg->state = ERROR_STATE;
- tasklet_schedule(&drv_data->pump_transfers);
-
+ dma_error_stop(drv_data, "dma_transfer: fifo overrun");
return IRQ_HANDLED;
}
/* Check for false positive timeout */
- if ((irq_status & SSSR_TINT) && DCSR(drv_data->tx_channel) & DCSR_RUN) {
+ if ((irq_status & SSSR_TINT)
+ && (DCSR(drv_data->tx_channel) & DCSR_RUN)) {
write_SSSR(SSSR_TINT, reg);
return IRQ_HANDLED;
}
if (irq_status & SSSR_TINT || drv_data->rx == drv_data->rx_end) {
- /* Clear and disable interrupts on SSP and DMA channels*/
- write_SSCR1(read_SSCR1(reg) & ~drv_data->dma_cr1, reg);
+ /* Clear and disable timeout interrupt, do the rest in
+ * dma_transfer_complete */
if (drv_data->ssp_type != PXA25x_SSP)
write_SSTO(0, reg);
- write_SSSR(drv_data->clear_sr, reg);
- DCSR(drv_data->tx_channel) = RESET_DMA_CHANNEL;
- DCSR(drv_data->rx_channel) = RESET_DMA_CHANNEL;
-
- if (wait_dma_channel_stop(drv_data->rx_channel) == 0)
- dev_err(&drv_data->pdev->dev,
- "dma_transfer: dma rx channel stop failed\n");
-
- if (wait_ssp_rx_stall(drv_data->ioaddr) == 0)
- dev_err(&drv_data->pdev->dev,
- "dma_transfer: ssp rx stall failed\n");
-
- unmap_dma_buffers(drv_data);
-
- /* Calculate number of trailing bytes, read them */
- trailing_sssr = read_SSSR(reg);
- if ((trailing_sssr & 0xf008) != 0xf000) {
- drv_data->rx = drv_data->rx_end -
- (((trailing_sssr >> 12) & 0x0f) + 1);
- drv_data->read(drv_data);
- }
- msg->actual_length += drv_data->len;
- /* Release chip select if requested, transfer delays are
- * handled in pump_transfers */
- if (drv_data->cs_change)
- drv_data->cs_control(PXA2XX_CS_DEASSERT);
-
- /* Move to next transfer */
- msg->state = next_transfer(drv_data);
-
- /* Schedule transfer tasklet */
- tasklet_schedule(&drv_data->pump_transfers);
+ /* finish this transfer, start the next */
+ dma_transfer_complete(drv_data);
return IRQ_HANDLED;
}
return IRQ_NONE;
}
-static irqreturn_t interrupt_transfer(struct driver_data *drv_data)
+static void int_error_stop(struct driver_data *drv_data, const char* msg)
{
- struct spi_message *msg = drv_data->cur_msg;
void *reg = drv_data->ioaddr;
- unsigned long limit = loops_per_jiffy << 1;
- u32 irq_status;
- u32 irq_mask = (read_SSCR1(reg) & SSCR1_TIE) ?
- drv_data->mask_sr : drv_data->mask_sr & ~SSSR_TFS;
-
- while ((irq_status = read_SSSR(reg) & irq_mask)) {
- if (irq_status & SSSR_ROR) {
+ /* Stop and reset SSP */
+ write_SSSR(drv_data->clear_sr, reg);
+ write_SSCR1(read_SSCR1(reg) & ~drv_data->int_cr1, reg);
+ if (drv_data->ssp_type != PXA25x_SSP)
+ write_SSTO(0, reg);
+ flush(drv_data);
+ write_SSCR0(read_SSCR0(reg) & ~SSCR0_SSE, reg);
- /* Clear and disable interrupts */
- write_SSCR0(read_SSCR0(reg) & ~SSCR0_SSE, reg);
- write_SSCR1(read_SSCR1(reg) & ~drv_data->int_cr1, reg);
- if (drv_data->ssp_type != PXA25x_SSP)
- write_SSTO(0, reg);
- write_SSSR(drv_data->clear_sr, reg);
+ dev_err(&drv_data->pdev->dev, "%s\n", msg);
- if (flush(drv_data) == 0)
- dev_err(&drv_data->pdev->dev,
- "interrupt_transfer: flush fail\n");
+ drv_data->cur_msg->state = ERROR_STATE;
+ tasklet_schedule(&drv_data->pump_transfers);
+}
- /* Stop the SSP */
+static void int_transfer_complete(struct driver_data *drv_data)
+{
+ void *reg = drv_data->ioaddr;
- dev_warn(&drv_data->pdev->dev,
- "interrupt_transfer: fifo overun\n");
+ /* Stop SSP */
+ write_SSSR(drv_data->clear_sr, reg);
+ write_SSCR1(read_SSCR1(reg) & ~drv_data->int_cr1, reg);
+ if (drv_data->ssp_type != PXA25x_SSP)
+ write_SSTO(0, reg);
- msg->state = ERROR_STATE;
- tasklet_schedule(&drv_data->pump_transfers);
+ /* Update total byte transfered return count actual bytes read */
+ drv_data->cur_msg->actual_length += drv_data->len -
+ (drv_data->rx_end - drv_data->rx);
- return IRQ_HANDLED;
- }
-
- /* Look for false positive timeout */
- if ((irq_status & SSSR_TINT)
- && (drv_data->rx < drv_data->rx_end))
- write_SSSR(SSSR_TINT, reg);
+ /* Release chip select if requested, transfer delays are
+ * handled in pump_transfers */
+ if (drv_data->cs_change)
+ drv_data->cs_control(PXA2XX_CS_DEASSERT);
- /* Pump data */
- drv_data->read(drv_data);
- drv_data->write(drv_data);
+ /* Move to next transfer */
+ drv_data->cur_msg->state = next_transfer(drv_data);
- if (drv_data->tx == drv_data->tx_end) {
- /* Disable tx interrupt */
- write_SSCR1(read_SSCR1(reg) & ~SSCR1_TIE, reg);
- irq_mask = drv_data->mask_sr & ~SSSR_TFS;
+ /* Schedule transfer tasklet */
+ tasklet_schedule(&drv_data->pump_transfers);
+}
- /* PXA25x_SSP has no timeout, read trailing bytes */
- if (drv_data->ssp_type == PXA25x_SSP) {
- while ((read_SSSR(reg) & SSSR_BSY) && limit--)
- drv_data->read(drv_data);
+static irqreturn_t interrupt_transfer(struct driver_data *drv_data)
+{
+ void *reg = drv_data->ioaddr;
- if (limit == 0)
- dev_err(&drv_data->pdev->dev,
- "interrupt_transfer: "
- "trailing byte read failed\n");
- }
- }
+ u32 irq_mask = (read_SSCR1(reg) & SSCR1_TIE) ?
+ drv_data->mask_sr : drv_data->mask_sr & ~SSSR_TFS;
- if ((irq_status & SSSR_TINT)
- || (drv_data->rx == drv_data->rx_end)) {
+ u32 irq_status = read_SSSR(reg) & irq_mask;
- /* Clear timeout */
- write_SSCR1(read_SSCR1(reg) & ~drv_data->int_cr1, reg);
- if (drv_data->ssp_type != PXA25x_SSP)
- write_SSTO(0, reg);
- write_SSSR(drv_data->clear_sr, reg);
+ if (irq_status & SSSR_ROR) {
+ int_error_stop(drv_data, "interrupt_transfer: fifo overrun");
+ return IRQ_HANDLED;
+ }
- /* Update total byte transfered */
- msg->actual_length += drv_data->len;
+ if (irq_status & SSSR_TINT) {
+ write_SSSR(SSSR_TINT, reg);
+ if (drv_data->read(drv_data)) {
+ int_transfer_complete(drv_data);
+ return IRQ_HANDLED;
+ }
+ }
- /* Release chip select if requested, transfer delays are
- * handled in pump_transfers */
- if (drv_data->cs_change)
- drv_data->cs_control(PXA2XX_CS_DEASSERT);
+ /* Drain rx fifo, Fill tx fifo and prevent overruns */
+ do {
+ if (drv_data->read(drv_data)) {
+ int_transfer_complete(drv_data);
+ return IRQ_HANDLED;
+ }
+ } while (drv_data->write(drv_data));
- /* Move to next transfer */
- msg->state = next_transfer(drv_data);
+ if (drv_data->read(drv_data)) {
+ int_transfer_complete(drv_data);
+ return IRQ_HANDLED;
+ }
- /* Schedule transfer tasklet */
- tasklet_schedule(&drv_data->pump_transfers);
+ if (drv_data->tx == drv_data->tx_end) {
+ write_SSCR1(read_SSCR1(reg) & ~SSCR1_TIE, reg);
+ /* PXA25x_SSP has no timeout, read trailing bytes */
+ if (drv_data->ssp_type == PXA25x_SSP) {
+ if (!wait_ssp_rx_stall(reg))
+ {
+ int_error_stop(drv_data, "interrupt_transfer: "
+ "rx stall failed");
+ return IRQ_HANDLED;
+ }
+ if (!drv_data->read(drv_data))
+ {
+ int_error_stop(drv_data,
+ "interrupt_transfer: "
+ "trailing byte read failed");
+ return IRQ_HANDLED;
+ }
+ int_transfer_complete(drv_data);
}
}
return IRQ_HANDLED;
}
-static irqreturn_t ssp_int(int irq, void *dev_id, struct pt_regs *regs)
+static irqreturn_t ssp_int(int irq, void *dev_id)
{
- struct driver_data *drv_data = (struct driver_data *)dev_id;
+ struct driver_data *drv_data = dev_id;
void *reg = drv_data->ioaddr;
if (!drv_data->cur_msg) {
write_SSSR(drv_data->clear_sr, reg);
dev_err(&drv_data->pdev->dev, "bad message state "
- "in interrupt handler");
+ "in interrupt handler\n");
/* Never fail */
return IRQ_HANDLED;
return drv_data->transfer_handler(drv_data);
}
+int set_dma_burst_and_threshold(struct chip_data *chip, struct spi_device *spi,
+ u8 bits_per_word, u32 *burst_code,
+ u32 *threshold)
+{
+ struct pxa2xx_spi_chip *chip_info =
+ (struct pxa2xx_spi_chip *)spi->controller_data;
+ int bytes_per_word;
+ int burst_bytes;
+ int thresh_words;
+ int req_burst_size;
+ int retval = 0;
+
+ /* Set the threshold (in registers) to equal the same amount of data
+ * as represented by burst size (in bytes). The computation below
+ * is (burst_size rounded up to nearest 8 byte, word or long word)
+ * divided by (bytes/register); the tx threshold is the inverse of
+ * the rx, so that there will always be enough data in the rx fifo
+ * to satisfy a burst, and there will always be enough space in the
+ * tx fifo to accept a burst (a tx burst will overwrite the fifo if
+ * there is not enough space), there must always remain enough empty
+ * space in the rx fifo for any data loaded to the tx fifo.
+ * Whenever burst_size (in bytes) equals bits/word, the fifo threshold
+ * will be 8, or half the fifo;
+ * The threshold can only be set to 2, 4 or 8, but not 16, because
+ * to burst 16 to the tx fifo, the fifo would have to be empty;
+ * however, the minimum fifo trigger level is 1, and the tx will
+ * request service when the fifo is at this level, with only 15 spaces.
+ */
+
+ /* find bytes/word */
+ if (bits_per_word <= 8)
+ bytes_per_word = 1;
+ else if (bits_per_word <= 16)
+ bytes_per_word = 2;
+ else
+ bytes_per_word = 4;
+
+ /* use struct pxa2xx_spi_chip->dma_burst_size if available */
+ if (chip_info)
+ req_burst_size = chip_info->dma_burst_size;
+ else {
+ switch (chip->dma_burst_size) {
+ default:
+ /* if the default burst size is not set,
+ * do it now */
+ chip->dma_burst_size = DCMD_BURST8;
+ case DCMD_BURST8:
+ req_burst_size = 8;
+ break;
+ case DCMD_BURST16:
+ req_burst_size = 16;
+ break;
+ case DCMD_BURST32:
+ req_burst_size = 32;
+ break;
+ }
+ }
+ if (req_burst_size <= 8) {
+ *burst_code = DCMD_BURST8;
+ burst_bytes = 8;
+ } else if (req_burst_size <= 16) {
+ if (bytes_per_word == 1) {
+ /* don't burst more than 1/2 the fifo */
+ *burst_code = DCMD_BURST8;
+ burst_bytes = 8;
+ retval = 1;
+ } else {
+ *burst_code = DCMD_BURST16;
+ burst_bytes = 16;
+ }
+ } else {
+ if (bytes_per_word == 1) {
+ /* don't burst more than 1/2 the fifo */
+ *burst_code = DCMD_BURST8;
+ burst_bytes = 8;
+ retval = 1;
+ } else if (bytes_per_word == 2) {
+ /* don't burst more than 1/2 the fifo */
+ *burst_code = DCMD_BURST16;
+ burst_bytes = 16;
+ retval = 1;
+ } else {
+ *burst_code = DCMD_BURST32;
+ burst_bytes = 32;
+ }
+ }
+
+ thresh_words = burst_bytes / bytes_per_word;
+
+ /* thresh_words will be between 2 and 8 */
+ *threshold = (SSCR1_RxTresh(thresh_words) & SSCR1_RFT)
+ | (SSCR1_TxTresh(16-thresh_words) & SSCR1_TFT);
+
+ return retval;
+}
+
static void pump_transfers(unsigned long data)
{
struct driver_data *drv_data = (struct driver_data *)data;
u8 bits = 0;
u32 speed = 0;
u32 cr0;
+ u32 cr1;
+ u32 dma_thresh = drv_data->cur_chip->dma_threshold;
+ u32 dma_burst = drv_data->cur_chip->dma_burst_size;
/* Get current state information */
message = drv_data->cur_msg;
udelay(previous->delay_usecs);
}
+ /* Check transfer length */
+ if (transfer->len > 8191)
+ {
+ dev_warn(&drv_data->pdev->dev, "pump_transfers: transfer "
+ "length greater than 8191\n");
+ message->status = -EINVAL;
+ giveback(drv_data);
+ return;
+ }
+
/* Setup the transfer state based on the type of transfer */
if (flush(drv_data) == 0) {
dev_err(&drv_data->pdev->dev, "pump_transfers: flush failed\n");
drv_data->rx_end = drv_data->rx + transfer->len;
drv_data->rx_dma = transfer->rx_dma;
drv_data->tx_dma = transfer->tx_dma;
- drv_data->len = transfer->len;
+ drv_data->len = transfer->len & DCMD_LENGTH;
drv_data->write = drv_data->tx ? chip->write : null_writer;
drv_data->read = drv_data->rx ? chip->read : null_reader;
drv_data->cs_change = transfer->cs_change;
/* Change speed and bit per word on a per transfer */
+ cr0 = chip->cr0;
if (transfer->speed_hz || transfer->bits_per_word) {
- /* Disable clock */
- write_SSCR0(chip->cr0 & ~SSCR0_SSE, reg);
- cr0 = chip->cr0;
bits = chip->bits_per_word;
speed = chip->speed_hz;
drv_data->write = drv_data->write != null_writer ?
u32_writer : null_writer;
}
+ /* if bits/word is changed in dma mode, then must check the
+ * thresholds and burst also */
+ if (chip->enable_dma) {
+ if (set_dma_burst_and_threshold(chip, message->spi,
+ bits, &dma_burst,
+ &dma_thresh))
+ if (printk_ratelimit())
+ dev_warn(&message->spi->dev,
+ "pump_transfer: "
+ "DMA burst size reduced to "
+ "match bits_per_word\n");
+ }
cr0 = clk_div
| SSCR0_Motorola
| SSCR0_DataSize(bits > 16 ? bits - 16 : bits)
| SSCR0_SSE
| (bits > 16 ? SSCR0_EDSS : 0);
-
- /* Start it back up */
- write_SSCR0(cr0, reg);
}
message->state = RUNNING_STATE;
/* No target address increment */
DCMD(drv_data->rx_channel) = DCMD_FLOWSRC
| drv_data->dma_width
- | chip->dma_burst_size
+ | dma_burst
| drv_data->len;
else
DCMD(drv_data->rx_channel) = DCMD_INCTRGADDR
| DCMD_FLOWSRC
| drv_data->dma_width
- | chip->dma_burst_size
+ | dma_burst
| drv_data->len;
/* Setup tx DMA Channel */
/* No source address increment */
DCMD(drv_data->tx_channel) = DCMD_FLOWTRG
| drv_data->dma_width
- | chip->dma_burst_size
+ | dma_burst
| drv_data->len;
else
DCMD(drv_data->tx_channel) = DCMD_INCSRCADDR
| DCMD_FLOWTRG
| drv_data->dma_width
- | chip->dma_burst_size
+ | dma_burst
| drv_data->len;
/* Enable dma end irqs on SSP to detect end of transfer */
/* Fix me, need to handle cs polarity */
drv_data->cs_control(PXA2XX_CS_ASSERT);
- /* Go baby, go */
+ /* Clear status and start DMA engine */
+ cr1 = chip->cr1 | dma_thresh | drv_data->dma_cr1;
write_SSSR(drv_data->clear_sr, reg);
DCSR(drv_data->rx_channel) |= DCSR_RUN;
DCSR(drv_data->tx_channel) |= DCSR_RUN;
- if (drv_data->ssp_type != PXA25x_SSP)
- write_SSTO(chip->timeout, reg);
- write_SSCR1(chip->cr1
- | chip->dma_threshold
- | drv_data->dma_cr1,
- reg);
} else {
/* Ensure we have the correct interrupt handler */
drv_data->transfer_handler = interrupt_transfer;
/* Fix me, need to handle cs polarity */
drv_data->cs_control(PXA2XX_CS_ASSERT);
- /* Go baby, go */
+ /* Clear status */
+ cr1 = chip->cr1 | chip->threshold | drv_data->int_cr1;
write_SSSR(drv_data->clear_sr, reg);
+ }
+
+ /* see if we need to reload the config registers */
+ if ((read_SSCR0(reg) != cr0)
+ || (read_SSCR1(reg) & SSCR1_CHANGE_MASK) !=
+ (cr1 & SSCR1_CHANGE_MASK)) {
+
+ write_SSCR0(cr0 & ~SSCR0_SSE, reg);
if (drv_data->ssp_type != PXA25x_SSP)
write_SSTO(chip->timeout, reg);
- write_SSCR1(chip->cr1
- | chip->threshold
- | drv_data->int_cr1,
- reg);
+ write_SSCR1(cr1, reg);
+ write_SSCR0(cr0, reg);
+ } else {
+ if (drv_data->ssp_type != PXA25x_SSP)
+ write_SSTO(chip->timeout, reg);
+ write_SSCR1(cr1, reg);
}
}
-static void pump_messages(void *data)
+static void pump_messages(struct work_struct *work)
{
- struct driver_data *drv_data = data;
+ struct driver_data *drv_data =
+ container_of(work, struct driver_data, pump_messages);
unsigned long flags;
/* Lock queue and check for queue work */
struct spi_transfer,
transfer_list);
- /* Setup the SSP using the per chip configuration */
+ /* prepare to setup the SSP, in pump_transfers, using the per
+ * chip configuration */
drv_data->cur_chip = spi_get_ctldata(drv_data->cur_msg->spi);
- restore_state(drv_data);
/* Mark as busy and launch transfers */
tasklet_schedule(&drv_data->pump_transfers);
spi->bits_per_word = 8;
if (drv_data->ssp_type != PXA25x_SSP
- && (spi->bits_per_word < 4 || spi->bits_per_word > 32))
+ && (spi->bits_per_word < 4 || spi->bits_per_word > 32)) {
+ dev_err(&spi->dev, "failed setup: ssp_type=%d, bits/wrd=%d "
+ "b/w not 4-32 for type non-PXA25x_SSP\n",
+ drv_data->ssp_type, spi->bits_per_word);
return -EINVAL;
- else if (spi->bits_per_word < 4 || spi->bits_per_word > 16)
+ }
+ else if (drv_data->ssp_type == PXA25x_SSP
+ && (spi->bits_per_word < 4
+ || spi->bits_per_word > 16)) {
+ dev_err(&spi->dev, "failed setup: ssp_type=%d, bits/wrd=%d "
+ "b/w not 4-16 for type PXA25x_SSP\n",
+ drv_data->ssp_type, spi->bits_per_word);
return -EINVAL;
+ }
- /* Only alloc (or use chip_info) on first setup */
+ /* Only alloc on first setup */
chip = spi_get_ctldata(spi);
- if (chip == NULL) {
+ if (!chip) {
chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
- if (!chip)
+ if (!chip) {
+ dev_err(&spi->dev,
+ "failed setup: can't allocate chip data\n");
return -ENOMEM;
+ }
chip->cs_control = null_cs_control;
chip->enable_dma = 0;
- chip->timeout = SSP_TIMEOUT(1000);
+ chip->timeout = 1000;
chip->threshold = SSCR1_RxTresh(1) | SSCR1_TxTresh(1);
chip->dma_burst_size = drv_data->master_info->enable_dma ?
DCMD_BURST8 : 0;
-
- chip_info = spi->controller_data;
}
+ /* protocol drivers may change the chip settings, so...
+ * if chip_info exists, use it */
+ chip_info = spi->controller_data;
+
/* chip_info isn't always needed */
+ chip->cr1 = 0;
if (chip_info) {
if (chip_info->cs_control)
chip->cs_control = chip_info->cs_control;
- chip->timeout = SSP_TIMEOUT(chip_info->timeout_microsecs);
+ chip->timeout = chip_info->timeout;
- chip->threshold = SSCR1_RxTresh(chip_info->rx_threshold)
- | SSCR1_TxTresh(chip_info->tx_threshold);
+ chip->threshold = (SSCR1_RxTresh(chip_info->rx_threshold) &
+ SSCR1_RFT) |
+ (SSCR1_TxTresh(chip_info->tx_threshold) &
+ SSCR1_TFT);
chip->enable_dma = chip_info->dma_burst_size != 0
&& drv_data->master_info->enable_dma;
chip->dma_threshold = 0;
- if (chip->enable_dma) {
- if (chip_info->dma_burst_size <= 8) {
- chip->dma_threshold = SSCR1_RxTresh(8)
- | SSCR1_TxTresh(8);
- chip->dma_burst_size = DCMD_BURST8;
- } else if (chip_info->dma_burst_size <= 16) {
- chip->dma_threshold = SSCR1_RxTresh(16)
- | SSCR1_TxTresh(16);
- chip->dma_burst_size = DCMD_BURST16;
- } else {
- chip->dma_threshold = SSCR1_RxTresh(32)
- | SSCR1_TxTresh(32);
- chip->dma_burst_size = DCMD_BURST32;
- }
- }
-
-
if (chip_info->enable_loopback)
chip->cr1 = SSCR1_LBM;
}
+ /* set dma burst and threshold outside of chip_info path so that if
+ * chip_info goes away after setting chip->enable_dma, the
+ * burst and threshold can still respond to changes in bits_per_word */
+ if (chip->enable_dma) {
+ /* set up legal burst and threshold for dma */
+ if (set_dma_burst_and_threshold(chip, spi, spi->bits_per_word,
+ &chip->dma_burst_size,
+ &chip->dma_threshold)) {
+ dev_warn(&spi->dev, "in setup: DMA burst size reduced "
+ "to match bits_per_word\n");
+ }
+ }
+
if (drv_data->ioaddr == SSP1_VIRT)
clk_div = SSP1_SerClkDiv(spi->max_speed_hz);
else if (drv_data->ioaddr == SSP2_VIRT)
else if (drv_data->ioaddr == SSP3_VIRT)
clk_div = SSP3_SerClkDiv(spi->max_speed_hz);
else
+ {
+ dev_err(&spi->dev, "failed setup: unknown IO address=0x%p\n",
+ drv_data->ioaddr);
return -ENODEV;
+ }
chip->speed_hz = spi->max_speed_hz;
chip->cr0 = clk_div
spi->bits_per_word - 16 : spi->bits_per_word)
| SSCR0_SSE
| (spi->bits_per_word > 16 ? SSCR0_EDSS : 0);
- chip->cr1 |= (((spi->mode & SPI_CPHA) != 0) << 4)
- | (((spi->mode & SPI_CPOL) != 0) << 3);
+ chip->cr1 &= ~(SSCR1_SPO | SSCR1_SPH);
+ chip->cr1 |= (((spi->mode & SPI_CPHA) != 0) ? SSCR1_SPH : 0)
+ | (((spi->mode & SPI_CPOL) != 0) ? SSCR1_SPO : 0);
/* NOTE: PXA25x_SSP _could_ use external clocking ... */
if (drv_data->ssp_type != PXA25x_SSP)
chip->write = u32_writer;
} else {
dev_err(&spi->dev, "invalid wordsize\n");
- kfree(chip);
return -ENODEV;
}
chip->bits_per_word = spi->bits_per_word;
tasklet_init(&drv_data->pump_transfers,
pump_transfers, (unsigned long)drv_data);
- INIT_WORK(&drv_data->pump_messages, pump_messages, drv_data);
+ INIT_WORK(&drv_data->pump_messages, pump_messages);
drv_data->workqueue = create_singlethread_workqueue(
drv_data->master->cdev.dev->bus_id);
if (drv_data->workqueue == NULL)
int status;
status = stop_queue(drv_data);
+ /* we are unloading the module or failing to load (only two calls
+ * to this routine), and neither call can handle a return value.
+ * However, destroy_workqueue calls flush_workqueue, and that will
+ * block until all work is done. If the reason that stop_queue
+ * timed out is that the work will never finish, then it does no
+ * good to call destroy_workqueue, so return anyway. */
if (status != 0)
return status;
/* Remove the queue */
status = destroy_queue(drv_data);
if (status != 0)
- return status;
+ /* the kernel does not check the return status of this
+ * this routine (mod->exit, within the kernel). Therefore
+ * nothing is gained by returning from here, the module is
+ * going away regardless, and we should not leave any more
+ * resources allocated than necessary. We cannot free the
+ * message memory in drv_data->queue, but we can release the
+ * resources below. I think the kernel should honor -EBUSY
+ * returns but... */
+ dev_err(&pdev->dev, "pxa2xx_spi_remove: workqueue will not "
+ "complete, message memory not freed\n");
/* Disable the SSP at the peripheral and SOC level */
write_SSCR0(0, drv_data->ioaddr);
git.openpandora.org / pandora-kernel.git / blobdiff