diff options
Diffstat (limited to 'drivers/spi/spi-pl022.c')
| -rw-r--r-- | drivers/spi/spi-pl022.c | 196 |
1 files changed, 175 insertions, 21 deletions
diff --git a/drivers/spi/spi-pl022.c b/drivers/spi/spi-pl022.c index 6abbe23..f8568b4 100644 --- a/drivers/spi/spi-pl022.c +++ b/drivers/spi/spi-pl022.c @@ -40,6 +40,9 @@ #include <linux/dma-mapping.h> #include <linux/scatterlist.h> #include <linux/pm_runtime.h> +#include <linux/gpio.h> +#include <linux/of_gpio.h> +#include <linux/pinctrl/consumer.h> /* * This macro is used to define some register default values. @@ -356,6 +359,8 @@ struct vendor_data { * @sgt_rx: scattertable for the RX transfer * @sgt_tx: scattertable for the TX transfer * @dummypage: a dummy page used for driving data on the bus with DMA + * @cur_cs: current chip select (gpio) + * @chipselects: list of chipselects (gpios) */ struct pl022 { struct amba_device *adev; @@ -363,6 +368,10 @@ struct pl022 { resource_size_t phybase; void __iomem *virtbase; struct clk *clk; + /* Two optional pin states - default & sleep */ + struct pinctrl *pinctrl; + struct pinctrl_state *pins_default; + struct pinctrl_state *pins_sleep; struct spi_master *master; struct pl022_ssp_controller *master_info; /* Message per-transfer pump */ @@ -389,6 +398,8 @@ struct pl022 { char *dummypage; bool dma_running; #endif + int cur_cs; + int *chipselects; }; /** @@ -433,6 +444,14 @@ static void null_cs_control(u32 command) pr_debug("pl022: dummy chip select control, CS=0x%x\n", command); } +static void pl022_cs_control(struct pl022 *pl022, u32 command) +{ + if (gpio_is_valid(pl022->cur_cs)) + gpio_set_value(pl022->cur_cs, command); + else + pl022->cur_chip->cs_control(command); +} + /** * giveback - current spi_message is over, schedule next message and call * callback of this message. Assumes that caller already @@ -479,7 +498,7 @@ static void giveback(struct pl022 *pl022) if (next_msg && next_msg->spi != pl022->cur_msg->spi) next_msg = NULL; if (!next_msg || pl022->cur_msg->state == STATE_ERROR) - pl022->cur_chip->cs_control(SSP_CHIP_DESELECT); + pl022_cs_control(pl022, SSP_CHIP_DESELECT); else pl022->next_msg_cs_active = true; @@ -818,8 +837,7 @@ static void dma_callback(void *data) /* Update total bytes transferred */ msg->actual_length += pl022->cur_transfer->len; if (pl022->cur_transfer->cs_change) - pl022->cur_chip-> - cs_control(SSP_CHIP_DESELECT); + pl022_cs_control(pl022, SSP_CHIP_DESELECT); /* Move to next transfer */ msg->state = next_transfer(pl022); @@ -1252,8 +1270,7 @@ static irqreturn_t pl022_interrupt_handler(int irq, void *dev_id) /* Update total bytes transferred */ msg->actual_length += pl022->cur_transfer->len; if (pl022->cur_transfer->cs_change) - pl022->cur_chip-> - cs_control(SSP_CHIP_DESELECT); + pl022_cs_control(pl022, SSP_CHIP_DESELECT); /* Move to next transfer */ msg->state = next_transfer(pl022); tasklet_schedule(&pl022->pump_transfers); @@ -1338,7 +1355,7 @@ static void pump_transfers(unsigned long data) /* Reselect chip select only if cs_change was requested */ if (previous->cs_change) - pl022->cur_chip->cs_control(SSP_CHIP_SELECT); + pl022_cs_control(pl022, SSP_CHIP_SELECT); } else { /* STATE_START */ message->state = STATE_RUNNING; @@ -1377,7 +1394,7 @@ static void do_interrupt_dma_transfer(struct pl022 *pl022) /* Enable target chip, if not already active */ if (!pl022->next_msg_cs_active) - pl022->cur_chip->cs_control(SSP_CHIP_SELECT); + pl022_cs_control(pl022, SSP_CHIP_SELECT); if (set_up_next_transfer(pl022, pl022->cur_transfer)) { /* Error path */ @@ -1429,12 +1446,12 @@ static void do_polling_transfer(struct pl022 *pl022) if (previous->delay_usecs) udelay(previous->delay_usecs); if (previous->cs_change) - pl022->cur_chip->cs_control(SSP_CHIP_SELECT); + pl022_cs_control(pl022, SSP_CHIP_SELECT); } else { /* STATE_START */ message->state = STATE_RUNNING; if (!pl022->next_msg_cs_active) - pl022->cur_chip->cs_control(SSP_CHIP_SELECT); + pl022_cs_control(pl022, SSP_CHIP_SELECT); } /* Configuration Changing Per Transfer */ @@ -1466,7 +1483,7 @@ static void do_polling_transfer(struct pl022 *pl022) /* Update total byte transferred */ message->actual_length += pl022->cur_transfer->len; if (pl022->cur_transfer->cs_change) - pl022->cur_chip->cs_control(SSP_CHIP_DESELECT); + pl022_cs_control(pl022, SSP_CHIP_DESELECT); /* Move to next transfer */ message->state = next_transfer(pl022); } @@ -1495,6 +1512,7 @@ static int pl022_transfer_one_message(struct spi_master *master, /* Setup the SPI using the per chip configuration */ pl022->cur_chip = spi_get_ctldata(msg->spi); + pl022->cur_cs = pl022->chipselects[msg->spi->chip_select]; restore_state(pl022); flush(pl022); @@ -1766,12 +1784,14 @@ static const struct pl022_config_chip pl022_default_chip_info = { static int pl022_setup(struct spi_device *spi) { struct pl022_config_chip const *chip_info; + struct pl022_config_chip chip_info_dt; struct chip_data *chip; struct ssp_clock_params clk_freq = { .cpsdvsr = 0, .scr = 0}; int status = 0; struct pl022 *pl022 = spi_master_get_devdata(spi->master); unsigned int bits = spi->bits_per_word; u32 tmp; + struct device_node *np = spi->dev.of_node; if (!spi->max_speed_hz) return -EINVAL; @@ -1794,10 +1814,32 @@ static int pl022_setup(struct spi_device *spi) chip_info = spi->controller_data; if (chip_info == NULL) { - chip_info = &pl022_default_chip_info; - /* spi_board_info.controller_data not is supplied */ - dev_dbg(&spi->dev, - "using default controller_data settings\n"); + if (np) { + chip_info_dt = pl022_default_chip_info; + + chip_info_dt.hierarchy = SSP_MASTER; + of_property_read_u32(np, "pl022,interface", + &chip_info_dt.iface); + of_property_read_u32(np, "pl022,com-mode", + &chip_info_dt.com_mode); + of_property_read_u32(np, "pl022,rx-level-trig", + &chip_info_dt.rx_lev_trig); + of_property_read_u32(np, "pl022,tx-level-trig", + &chip_info_dt.tx_lev_trig); + of_property_read_u32(np, "pl022,ctrl-len", + &chip_info_dt.ctrl_len); + of_property_read_u32(np, "pl022,wait-state", + &chip_info_dt.wait_state); + of_property_read_u32(np, "pl022,duplex", + &chip_info_dt.duplex); + + chip_info = &chip_info_dt; + } else { + chip_info = &pl022_default_chip_info; + /* spi_board_info.controller_data not is supplied */ + dev_dbg(&spi->dev, + "using default controller_data settings\n"); + } } else dev_dbg(&spi->dev, "using user supplied controller_data settings\n"); @@ -1840,8 +1882,9 @@ static int pl022_setup(struct spi_device *spi) chip->xfer_type = chip_info->com_mode; if (!chip_info->cs_control) { chip->cs_control = null_cs_control; - dev_warn(&spi->dev, - "chip select function is NULL for this chip\n"); + if (!gpio_is_valid(pl022->chipselects[spi->chip_select])) + dev_warn(&spi->dev, + "invalid chip select\n"); } else chip->cs_control = chip_info->cs_control; @@ -1986,6 +2029,34 @@ static void pl022_cleanup(struct spi_device *spi) kfree(chip); } +static struct pl022_ssp_controller * +pl022_platform_data_dt_get(struct device *dev) +{ + struct device_node *np = dev->of_node; + struct pl022_ssp_controller *pd; + u32 tmp; + + if (!np) { + dev_err(dev, "no dt node defined\n"); + return NULL; + } + + pd = devm_kzalloc(dev, sizeof(struct pl022_ssp_controller), GFP_KERNEL); + if (!pd) { + dev_err(dev, "cannot allocate platform data memory\n"); + return NULL; + } + + pd->bus_id = -1; + of_property_read_u32(np, "num-cs", &tmp); + pd->num_chipselect = tmp; + of_property_read_u32(np, "pl022,autosuspend-delay", + &pd->autosuspend_delay); + pd->rt = of_property_read_bool(np, "pl022,rt"); + + return pd; +} + static int __devinit pl022_probe(struct amba_device *adev, const struct amba_id *id) { @@ -1993,12 +2064,24 @@ pl022_probe(struct amba_device *adev, const struct amba_id *id) struct pl022_ssp_controller *platform_info = adev->dev.platform_data; struct spi_master *master; struct pl022 *pl022 = NULL; /*Data for this driver */ - int status = 0; + struct device_node *np = adev->dev.of_node; + int status = 0, i, num_cs; dev_info(&adev->dev, "ARM PL022 driver, device ID: 0x%08x\n", adev->periphid); - if (platform_info == NULL) { - dev_err(&adev->dev, "probe - no platform data supplied\n"); + if (!platform_info && IS_ENABLED(CONFIG_OF)) + platform_info = pl022_platform_data_dt_get(dev); + + if (!platform_info) { + dev_err(dev, "probe: no platform data defined\n"); + status = -ENODEV; + goto err_no_pdata; + } + + if (platform_info->num_chipselect) { + num_cs = platform_info->num_chipselect; + } else { + dev_err(dev, "probe: no chip select defined\n"); status = -ENODEV; goto err_no_pdata; } @@ -2016,19 +2099,71 @@ pl022_probe(struct amba_device *adev, const struct amba_id *id) pl022->master_info = platform_info; pl022->adev = adev; pl022->vendor = id->data; + pl022->chipselects = devm_kzalloc(dev, num_cs * sizeof(int), + GFP_KERNEL); + + pl022->pinctrl = devm_pinctrl_get(dev); + if (IS_ERR(pl022->pinctrl)) { + status = PTR_ERR(pl022->pinctrl); + goto err_no_pinctrl; + } + + pl022->pins_default = pinctrl_lookup_state(pl022->pinctrl, + PINCTRL_STATE_DEFAULT); + /* enable pins to be muxed in and configured */ + if (!IS_ERR(pl022->pins_default)) { + status = pinctrl_select_state(pl022->pinctrl, + pl022->pins_default); + if (status) + dev_err(dev, "could not set default pins\n"); + } else + dev_err(dev, "could not get default pinstate\n"); + + pl022->pins_sleep = pinctrl_lookup_state(pl022->pinctrl, + PINCTRL_STATE_SLEEP); + if (IS_ERR(pl022->pins_sleep)) + dev_dbg(dev, "could not get sleep pinstate\n"); /* * Bus Number Which has been Assigned to this SSP controller * on this board */ master->bus_num = platform_info->bus_id; - master->num_chipselect = platform_info->num_chipselect; + master->num_chipselect = num_cs; master->cleanup = pl022_cleanup; master->setup = pl022_setup; master->prepare_transfer_hardware = pl022_prepare_transfer_hardware; master->transfer_one_message = pl022_transfer_one_message; master->unprepare_transfer_hardware = pl022_unprepare_transfer_hardware; master->rt = platform_info->rt; + master->dev.of_node = dev->of_node; + + if (platform_info->num_chipselect && platform_info->chipselects) { + for (i = 0; i < num_cs; i++) + pl022->chipselects[i] = platform_info->chipselects[i]; + } else if (IS_ENABLED(CONFIG_OF)) { + for (i = 0; i < num_cs; i++) { + int cs_gpio = of_get_named_gpio(np, "cs-gpios", i); + + if (cs_gpio == -EPROBE_DEFER) { + status = -EPROBE_DEFER; + goto err_no_gpio; + } + + pl022->chipselects[i] = cs_gpio; + + if (gpio_is_valid(cs_gpio)) { + if (gpio_request(cs_gpio, "ssp-pl022")) + dev_err(&adev->dev, + "could not request %d gpio\n", + cs_gpio); + else if (gpio_direction_output(cs_gpio, 1)) + dev_err(&adev->dev, + "could set gpio %d as output\n", + cs_gpio); + } + } + } /* * Supports mode 0-3, loopback, and active low CS. Transfers are @@ -2137,6 +2272,8 @@ pl022_probe(struct amba_device *adev, const struct amba_id *id) err_no_ioremap: amba_release_regions(adev); err_no_ioregion: + err_no_gpio: + err_no_pinctrl: spi_master_put(master); err_no_master: err_no_pdata: @@ -2170,7 +2307,6 @@ pl022_remove(struct amba_device *adev) amba_release_regions(adev); tasklet_disable(&pl022->pump_transfers); spi_unregister_master(pl022->master); - spi_master_put(pl022->master); amba_set_drvdata(adev, NULL); return 0; } @@ -2211,15 +2347,33 @@ static int pl022_resume(struct device *dev) static int pl022_runtime_suspend(struct device *dev) { struct pl022 *pl022 = dev_get_drvdata(dev); + int status = 0; clk_disable(pl022->clk); + /* Optionally let pins go into sleep states */ + if (!IS_ERR(pl022->pins_sleep)) { + status = pinctrl_select_state(pl022->pinctrl, + pl022->pins_sleep); + if (status) + dev_err(dev, "could not set pins to sleep state\n"); + } + return 0; } static int pl022_runtime_resume(struct device *dev) { struct pl022 *pl022 = dev_get_drvdata(dev); + int status = 0; + + /* Optionaly enable pins to be muxed in and configured */ + if (!IS_ERR(pl022->pins_default)) { + status = pinctrl_select_state(pl022->pinctrl, + pl022->pins_default); + if (status) + dev_err(dev, "could not set default pins\n"); + } clk_enable(pl022->clk); |