diff options
author | Linus Torvalds | 2015-04-13 15:05:40 -0700 |
---|---|---|
committer | Linus Torvalds | 2015-04-13 15:05:40 -0700 |
commit | 0055dc5b23cc1738fc2f14221cf922a83057d8fb (patch) | |
tree | 791ace137da6784403804b15cd8195fd51a1a4a0 /drivers/spi/spi-dw.c | |
parent | 1b57c7c2fbb81763cd4a6940c8530c98022c409c (diff) | |
parent | 56afdb70ca9140cdcbdcf01870f3e4e2e8be17f5 (diff) |
Merge tag 'spi-v4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
Pull spi updates from Mark Brown:
"Only one framework update this time around, a change from Lars-Peter
to move full to pm_ops and remove the legacy bus PM ops. Otherwise
it's all driver updates:
- make the spidev driver complain loudly if registered as spidev with
DT rather than with a compatible string, hopefully helping people
avoid making that mistake.
- error handling and robustness fixes for the Designware and Intel
MID drivers from Andy Shevchenko.
- substantial performance improvements for the Raspberry Pi driver
from Martin Sperl.
- several new features for spidev_test from Adrian Remonda and Ian
Abbott"
* tag 'spi-v4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (75 commits)
spi: bcm2835: enabling polling mode for transfers shorter than 30us
spi: bcm2835: transform native-cs to gpio-cs on first spi_setup
spi: img-spfi: Control CS lines with GPIO
spi: img-spfi: Reset controller after each message
spi: img-spfi: Implement a handle_err() callback
spi: img-spfi: Setup TRANSACTION register before CONTROL register
spi: Make master->handle_err() callback optional to avoid crashes
spi: img-spfi: Limit bit clock to 1/4th of input clock
spi: img-spfi: Implement a prepare_message() callback
spi: fsl-dspi: Add ~50ns delay between cs and sck
spi: fsl-dspi: Add cs-sck delays
spi: fsl-dspi: Fix clock rate scale values
spi: signedness bug in qspi_trigger_transfer_out_int()
spi: imx: read back the RX/TX watermark levels earlier
spi: spi-bfin5xx: Initialize cr_width in bfin_spi_pump_transfers()
spi: bitbang: only toggle bitchanges
spi: pxa2xx: missing break in pxa2xx_ssp_get_clk_div()
spi: fsl-dspi: Fix clock rate scale values
spi: Using Trigger number to transmit/receive data
spi: bcm2835: fill FIFO before enabling interrupts to reduce interrupts/message
...
Diffstat (limited to 'drivers/spi/spi-dw.c')
-rw-r--r-- | drivers/spi/spi-dw.c | 306 |
1 files changed, 92 insertions, 214 deletions
diff --git a/drivers/spi/spi-dw.c b/drivers/spi/spi-dw.c index 4847afba89f4..8d67d03c71eb 100644 --- a/drivers/spi/spi-dw.c +++ b/drivers/spi/spi-dw.c @@ -28,11 +28,6 @@ #include <linux/debugfs.h> #endif -#define START_STATE ((void *)0) -#define RUNNING_STATE ((void *)1) -#define DONE_STATE ((void *)2) -#define ERROR_STATE ((void *)-1) - /* Slave spi_dev related */ struct chip_data { u16 cr0; @@ -143,13 +138,26 @@ static inline void dw_spi_debugfs_remove(struct dw_spi *dws) } #endif /* CONFIG_DEBUG_FS */ +static void dw_spi_set_cs(struct spi_device *spi, bool enable) +{ + struct dw_spi *dws = spi_master_get_devdata(spi->master); + struct chip_data *chip = spi_get_ctldata(spi); + + /* Chip select logic is inverted from spi_set_cs() */ + if (chip && chip->cs_control) + chip->cs_control(!enable); + + if (!enable) + dw_writel(dws, DW_SPI_SER, BIT(spi->chip_select)); +} + /* Return the max entries we can fill into tx fifo */ static inline u32 tx_max(struct dw_spi *dws) { u32 tx_left, tx_room, rxtx_gap; tx_left = (dws->tx_end - dws->tx) / dws->n_bytes; - tx_room = dws->fifo_len - dw_readw(dws, DW_SPI_TXFLR); + tx_room = dws->fifo_len - dw_readl(dws, DW_SPI_TXFLR); /* * Another concern is about the tx/rx mismatch, we @@ -170,7 +178,7 @@ static inline u32 rx_max(struct dw_spi *dws) { u32 rx_left = (dws->rx_end - dws->rx) / dws->n_bytes; - return min_t(u32, rx_left, dw_readw(dws, DW_SPI_RXFLR)); + return min_t(u32, rx_left, dw_readl(dws, DW_SPI_RXFLR)); } static void dw_writer(struct dw_spi *dws) @@ -186,7 +194,7 @@ static void dw_writer(struct dw_spi *dws) else txw = *(u16 *)(dws->tx); } - dw_writew(dws, DW_SPI_DR, txw); + dw_writel(dws, DW_SPI_DR, txw); dws->tx += dws->n_bytes; } } @@ -197,7 +205,7 @@ static void dw_reader(struct dw_spi *dws) u16 rxw; while (max--) { - rxw = dw_readw(dws, DW_SPI_DR); + rxw = dw_readl(dws, DW_SPI_DR); /* Care rx only if the transfer's original "rx" is not null */ if (dws->rx_end - dws->len) { if (dws->n_bytes == 1) @@ -209,103 +217,22 @@ static void dw_reader(struct dw_spi *dws) } } -static void *next_transfer(struct dw_spi *dws) -{ - struct spi_message *msg = dws->cur_msg; - struct spi_transfer *trans = dws->cur_transfer; - - /* Move to next transfer */ - if (trans->transfer_list.next != &msg->transfers) { - dws->cur_transfer = - list_entry(trans->transfer_list.next, - struct spi_transfer, - transfer_list); - return RUNNING_STATE; - } - - return DONE_STATE; -} - -/* - * Note: first step is the protocol driver prepares - * a dma-capable memory, and this func just need translate - * the virt addr to physical - */ -static int map_dma_buffers(struct dw_spi *dws) -{ - if (!dws->cur_msg->is_dma_mapped - || !dws->dma_inited - || !dws->cur_chip->enable_dma - || !dws->dma_ops) - return 0; - - if (dws->cur_transfer->tx_dma) - dws->tx_dma = dws->cur_transfer->tx_dma; - - if (dws->cur_transfer->rx_dma) - dws->rx_dma = dws->cur_transfer->rx_dma; - - return 1; -} - -/* Caller already set message->status; dma and pio irqs are blocked */ -static void giveback(struct dw_spi *dws) -{ - struct spi_transfer *last_transfer; - struct spi_message *msg; - - msg = dws->cur_msg; - dws->cur_msg = NULL; - dws->cur_transfer = NULL; - dws->prev_chip = dws->cur_chip; - dws->cur_chip = NULL; - dws->dma_mapped = 0; - - last_transfer = list_last_entry(&msg->transfers, struct spi_transfer, - transfer_list); - - if (!last_transfer->cs_change) - spi_chip_sel(dws, msg->spi, 0); - - spi_finalize_current_message(dws->master); -} - static void int_error_stop(struct dw_spi *dws, const char *msg) { - /* Stop the hw */ - spi_enable_chip(dws, 0); + spi_reset_chip(dws); dev_err(&dws->master->dev, "%s\n", msg); - dws->cur_msg->state = ERROR_STATE; - tasklet_schedule(&dws->pump_transfers); + dws->master->cur_msg->status = -EIO; + spi_finalize_current_transfer(dws->master); } -void dw_spi_xfer_done(struct dw_spi *dws) -{ - /* Update total byte transferred return count actual bytes read */ - dws->cur_msg->actual_length += dws->len; - - /* Move to next transfer */ - dws->cur_msg->state = next_transfer(dws); - - /* Handle end of message */ - if (dws->cur_msg->state == DONE_STATE) { - dws->cur_msg->status = 0; - giveback(dws); - } else - tasklet_schedule(&dws->pump_transfers); -} -EXPORT_SYMBOL_GPL(dw_spi_xfer_done); - static irqreturn_t interrupt_transfer(struct dw_spi *dws) { - u16 irq_status = dw_readw(dws, DW_SPI_ISR); + u16 irq_status = dw_readl(dws, DW_SPI_ISR); /* Error handling */ if (irq_status & (SPI_INT_TXOI | SPI_INT_RXOI | SPI_INT_RXUI)) { - dw_readw(dws, DW_SPI_TXOICR); - dw_readw(dws, DW_SPI_RXOICR); - dw_readw(dws, DW_SPI_RXUICR); + dw_readl(dws, DW_SPI_ICR); int_error_stop(dws, "interrupt_transfer: fifo overrun/underrun"); return IRQ_HANDLED; } @@ -313,7 +240,7 @@ static irqreturn_t interrupt_transfer(struct dw_spi *dws) dw_reader(dws); if (dws->rx_end == dws->rx) { spi_mask_intr(dws, SPI_INT_TXEI); - dw_spi_xfer_done(dws); + spi_finalize_current_transfer(dws->master); return IRQ_HANDLED; } if (irq_status & SPI_INT_TXEI) { @@ -328,13 +255,14 @@ static irqreturn_t interrupt_transfer(struct dw_spi *dws) static irqreturn_t dw_spi_irq(int irq, void *dev_id) { - struct dw_spi *dws = dev_id; - u16 irq_status = dw_readw(dws, DW_SPI_ISR) & 0x3f; + struct spi_master *master = dev_id; + struct dw_spi *dws = spi_master_get_devdata(master); + u16 irq_status = dw_readl(dws, DW_SPI_ISR) & 0x3f; if (!irq_status) return IRQ_NONE; - if (!dws->cur_msg) { + if (!master->cur_msg) { spi_mask_intr(dws, SPI_INT_TXEI); return IRQ_HANDLED; } @@ -343,7 +271,7 @@ static irqreturn_t dw_spi_irq(int irq, void *dev_id) } /* Must be called inside pump_transfers() */ -static void poll_transfer(struct dw_spi *dws) +static int poll_transfer(struct dw_spi *dws) { do { dw_writer(dws); @@ -351,64 +279,32 @@ static void poll_transfer(struct dw_spi *dws) cpu_relax(); } while (dws->rx_end > dws->rx); - dw_spi_xfer_done(dws); + return 0; } -static void pump_transfers(unsigned long data) +static int dw_spi_transfer_one(struct spi_master *master, + struct spi_device *spi, struct spi_transfer *transfer) { - struct dw_spi *dws = (struct dw_spi *)data; - struct spi_message *message = NULL; - struct spi_transfer *transfer = NULL; - struct spi_transfer *previous = NULL; - struct spi_device *spi = NULL; - struct chip_data *chip = NULL; - u8 bits = 0; + struct dw_spi *dws = spi_master_get_devdata(master); + struct chip_data *chip = spi_get_ctldata(spi); u8 imask = 0; - u8 cs_change = 0; - u16 txint_level = 0; + u16 txlevel = 0; u16 clk_div = 0; u32 speed = 0; u32 cr0 = 0; + int ret; - /* Get current state information */ - message = dws->cur_msg; - transfer = dws->cur_transfer; - chip = dws->cur_chip; - spi = message->spi; - - if (message->state == ERROR_STATE) { - message->status = -EIO; - goto early_exit; - } - - /* Handle end of message */ - if (message->state == DONE_STATE) { - message->status = 0; - goto early_exit; - } - - /* Delay if requested at end of transfer */ - if (message->state == RUNNING_STATE) { - previous = list_entry(transfer->transfer_list.prev, - struct spi_transfer, - transfer_list); - if (previous->delay_usecs) - udelay(previous->delay_usecs); - } - + dws->dma_mapped = 0; dws->n_bytes = chip->n_bytes; dws->dma_width = chip->dma_width; - dws->cs_control = chip->cs_control; - dws->rx_dma = transfer->rx_dma; - dws->tx_dma = transfer->tx_dma; dws->tx = (void *)transfer->tx_buf; dws->tx_end = dws->tx + transfer->len; dws->rx = transfer->rx_buf; dws->rx_end = dws->rx + transfer->len; - dws->len = dws->cur_transfer->len; - if (chip != dws->prev_chip) - cs_change = 1; + dws->len = transfer->len; + + spi_enable_chip(dws, 0); cr0 = chip->cr0; @@ -416,32 +312,37 @@ static void pump_transfers(unsigned long data) if (transfer->speed_hz) { speed = chip->speed_hz; - if ((transfer->speed_hz != speed) || (!chip->clk_div)) { + if ((transfer->speed_hz != speed) || !chip->clk_div) { speed = transfer->speed_hz; /* clk_div doesn't support odd number */ - clk_div = dws->max_freq / speed; - clk_div = (clk_div + 1) & 0xfffe; + clk_div = (dws->max_freq / speed + 1) & 0xfffe; chip->speed_hz = speed; chip->clk_div = clk_div; + + spi_set_clk(dws, chip->clk_div); } } if (transfer->bits_per_word) { - bits = transfer->bits_per_word; - dws->n_bytes = dws->dma_width = bits >> 3; - cr0 = (bits - 1) + if (transfer->bits_per_word == 8) { + dws->n_bytes = 1; + dws->dma_width = 1; + } else if (transfer->bits_per_word == 16) { + dws->n_bytes = 2; + dws->dma_width = 2; + } + cr0 = (transfer->bits_per_word - 1) | (chip->type << SPI_FRF_OFFSET) | (spi->mode << SPI_MODE_OFFSET) | (chip->tmode << SPI_TMOD_OFFSET); } - message->state = RUNNING_STATE; /* * Adjust transfer mode if necessary. Requires platform dependent * chipselect mechanism. */ - if (dws->cs_control) { + if (chip->cs_control) { if (dws->rx && dws->tx) chip->tmode = SPI_TMOD_TR; else if (dws->rx) @@ -453,80 +354,60 @@ static void pump_transfers(unsigned long data) cr0 |= (chip->tmode << SPI_TMOD_OFFSET); } + dw_writel(dws, DW_SPI_CTRL0, cr0); + /* Check if current transfer is a DMA transaction */ - dws->dma_mapped = map_dma_buffers(dws); + if (master->can_dma && master->can_dma(master, spi, transfer)) + dws->dma_mapped = master->cur_msg_mapped; + + /* For poll mode just disable all interrupts */ + spi_mask_intr(dws, 0xff); /* * Interrupt mode * we only need set the TXEI IRQ, as TX/RX always happen syncronizely */ - if (!dws->dma_mapped && !chip->poll_mode) { - int templen = dws->len / dws->n_bytes; - - txint_level = dws->fifo_len / 2; - txint_level = (templen > txint_level) ? txint_level : templen; + if (dws->dma_mapped) { + ret = dws->dma_ops->dma_setup(dws, transfer); + if (ret < 0) { + spi_enable_chip(dws, 1); + return ret; + } + } else if (!chip->poll_mode) { + txlevel = min_t(u16, dws->fifo_len / 2, dws->len / dws->n_bytes); + dw_writel(dws, DW_SPI_TXFLTR, txlevel); + /* Set the interrupt mask */ imask |= SPI_INT_TXEI | SPI_INT_TXOI | SPI_INT_RXUI | SPI_INT_RXOI; + spi_umask_intr(dws, imask); + dws->transfer_handler = interrupt_transfer; } - /* - * Reprogram registers only if - * 1. chip select changes - * 2. clk_div is changed - * 3. control value changes - */ - if (dw_readw(dws, DW_SPI_CTRL0) != cr0 || cs_change || clk_div || imask) { - spi_enable_chip(dws, 0); - - if (dw_readw(dws, DW_SPI_CTRL0) != cr0) - dw_writew(dws, DW_SPI_CTRL0, cr0); - - spi_set_clk(dws, clk_div ? clk_div : chip->clk_div); - spi_chip_sel(dws, spi, 1); - - /* Set the interrupt mask, for poll mode just disable all int */ - spi_mask_intr(dws, 0xff); - if (imask) - spi_umask_intr(dws, imask); - if (txint_level) - dw_writew(dws, DW_SPI_TXFLTR, txint_level); + spi_enable_chip(dws, 1); - spi_enable_chip(dws, 1); - if (cs_change) - dws->prev_chip = chip; + if (dws->dma_mapped) { + ret = dws->dma_ops->dma_transfer(dws, transfer); + if (ret < 0) + return ret; } - if (dws->dma_mapped) - dws->dma_ops->dma_transfer(dws, cs_change); - if (chip->poll_mode) - poll_transfer(dws); - - return; + return poll_transfer(dws); -early_exit: - giveback(dws); + return 1; } -static int dw_spi_transfer_one_message(struct spi_master *master, +static void dw_spi_handle_err(struct spi_master *master, struct spi_message *msg) { struct dw_spi *dws = spi_master_get_devdata(master); - dws->cur_msg = msg; - /* Initial message state */ - dws->cur_msg->state = START_STATE; - dws->cur_transfer = list_entry(dws->cur_msg->transfers.next, - struct spi_transfer, - transfer_list); - dws->cur_chip = spi_get_ctldata(dws->cur_msg->spi); - - /* Launch transfers */ - tasklet_schedule(&dws->pump_transfers); + if (dws->dma_mapped) + dws->dma_ops->dma_stop(dws); - return 0; + spi_reset_chip(dws); } /* This may be called twice for each spi dev */ @@ -561,8 +442,6 @@ static int dw_spi_setup(struct spi_device *spi) chip->rx_threshold = 0; chip->tx_threshold = 0; - - chip->enable_dma = chip_info->enable_dma; } if (spi->bits_per_word == 8) { @@ -610,9 +489,7 @@ static void dw_spi_cleanup(struct spi_device *spi) /* Restart the controller, disable all interrupts, clean rx fifo */ static void spi_hw_init(struct device *dev, struct dw_spi *dws) { - spi_enable_chip(dws, 0); - spi_mask_intr(dws, 0xff); - spi_enable_chip(dws, 1); + spi_reset_chip(dws); /* * Try to detect the FIFO depth if not set by interface driver, @@ -622,11 +499,11 @@ static void spi_hw_init(struct device *dev, struct dw_spi *dws) u32 fifo; for (fifo = 1; fifo < 256; fifo++) { - dw_writew(dws, DW_SPI_TXFLTR, fifo); - if (fifo != dw_readw(dws, DW_SPI_TXFLTR)) + dw_writel(dws, DW_SPI_TXFLTR, fifo); + if (fifo != dw_readl(dws, DW_SPI_TXFLTR)) break; } - dw_writew(dws, DW_SPI_TXFLTR, 0); + dw_writel(dws, DW_SPI_TXFLTR, 0); dws->fifo_len = (fifo == 1) ? 0 : fifo; dev_dbg(dev, "Detected FIFO size: %u bytes\n", dws->fifo_len); @@ -646,13 +523,12 @@ int dw_spi_add_host(struct device *dev, struct dw_spi *dws) dws->master = master; dws->type = SSI_MOTO_SPI; - dws->prev_chip = NULL; dws->dma_inited = 0; dws->dma_addr = (dma_addr_t)(dws->paddr + 0x60); snprintf(dws->name, sizeof(dws->name), "dw_spi%d", dws->bus_num); ret = devm_request_irq(dev, dws->irq, dw_spi_irq, IRQF_SHARED, - dws->name, dws); + dws->name, master); if (ret < 0) { dev_err(&master->dev, "can not get IRQ\n"); goto err_free_master; @@ -664,7 +540,9 @@ int dw_spi_add_host(struct device *dev, struct dw_spi *dws) master->num_chipselect = dws->num_cs; master->setup = dw_spi_setup; master->cleanup = dw_spi_cleanup; - master->transfer_one_message = dw_spi_transfer_one_message; + master->set_cs = dw_spi_set_cs; + master->transfer_one = dw_spi_transfer_one; + master->handle_err = dw_spi_handle_err; master->max_speed_hz = dws->max_freq; master->dev.of_node = dev->of_node; @@ -676,11 +554,11 @@ int dw_spi_add_host(struct device *dev, struct dw_spi *dws) if (ret) { dev_warn(dev, "DMA init failed\n"); dws->dma_inited = 0; + } else { + master->can_dma = dws->dma_ops->can_dma; } } - tasklet_init(&dws->pump_transfers, pump_transfers, (unsigned long)dws); - spi_master_set_devdata(master, dws); ret = devm_spi_register_master(dev, master); if (ret) { |