diff options
Diffstat (limited to 'drivers/spi/spi.c')
| -rw-r--r-- | drivers/spi/spi.c | 145 |
1 files changed, 67 insertions, 78 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 7b213faa0a2b..20b5b2754830 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -28,6 +28,7 @@ #include <linux/slab.h> #include <linux/mod_devicetable.h> #include <linux/spi/spi.h> +#include <linux/spi/spi-mem.h> #include <linux/of_gpio.h> #include <linux/pm_runtime.h> #include <linux/pm_domain.h> @@ -46,6 +47,8 @@ #define CREATE_TRACE_POINTS #include <trace/events/spi.h> +#include "internals.h" + static DEFINE_IDR(spi_master_idr); static void spidev_release(struct device *dev) @@ -740,9 +743,9 @@ static void spi_set_cs(struct spi_device *spi, bool enable) } #ifdef CONFIG_HAS_DMA -static int spi_map_buf(struct spi_controller *ctlr, struct device *dev, - struct sg_table *sgt, void *buf, size_t len, - enum dma_data_direction dir) +int spi_map_buf(struct spi_controller *ctlr, struct device *dev, + struct sg_table *sgt, void *buf, size_t len, + enum dma_data_direction dir) { const bool vmalloced_buf = is_vmalloc_addr(buf); unsigned int max_seg_size = dma_get_max_seg_size(dev); @@ -821,8 +824,8 @@ static int spi_map_buf(struct spi_controller *ctlr, struct device *dev, return 0; } -static void spi_unmap_buf(struct spi_controller *ctlr, struct device *dev, - struct sg_table *sgt, enum dma_data_direction dir) +void spi_unmap_buf(struct spi_controller *ctlr, struct device *dev, + struct sg_table *sgt, enum dma_data_direction dir) { if (sgt->orig_nents) { dma_unmap_sg(dev, sgt->sgl, sgt->orig_nents, dir); @@ -907,19 +910,6 @@ static int __spi_unmap_msg(struct spi_controller *ctlr, struct spi_message *msg) return 0; } #else /* !CONFIG_HAS_DMA */ -static inline int spi_map_buf(struct spi_controller *ctlr, struct device *dev, - struct sg_table *sgt, void *buf, size_t len, - enum dma_data_direction dir) -{ - return -EINVAL; -} - -static inline void spi_unmap_buf(struct spi_controller *ctlr, - struct device *dev, struct sg_table *sgt, - enum dma_data_direction dir) -{ -} - static inline int __spi_map_msg(struct spi_controller *ctlr, struct spi_message *msg) { @@ -1222,6 +1212,7 @@ static void __spi_pump_messages(struct spi_controller *ctlr, bool in_kthread) if (!was_busy && ctlr->auto_runtime_pm) { ret = pm_runtime_get_sync(ctlr->dev.parent); if (ret < 0) { + pm_runtime_put_noidle(ctlr->dev.parent); dev_err(&ctlr->dev, "Failed to power device: %d\n", ret); mutex_unlock(&ctlr->io_mutex); @@ -1533,6 +1524,22 @@ err_init_queue: return ret; } +/** + * spi_flush_queue - Send all pending messages in the queue from the callers' + * context + * @ctlr: controller to process queue for + * + * This should be used when one wants to ensure all pending messages have been + * sent before doing something. Is used by the spi-mem code to make sure SPI + * memory operations do not preempt regular SPI transfers that have been queued + * before the spi-mem operation. + */ +void spi_flush_queue(struct spi_controller *ctlr) +{ + if (ctlr->transfer == spi_queued_transfer) + __spi_pump_messages(ctlr, false); +} + /*-------------------------------------------------------------------------*/ #if defined(CONFIG_OF) @@ -2063,6 +2070,26 @@ static int of_spi_register_master(struct spi_controller *ctlr) } #endif +static int spi_controller_check_ops(struct spi_controller *ctlr) +{ + /* + * The controller may implement only the high-level SPI-memory like + * operations if it does not support regular SPI transfers, and this is + * valid use case. + * If ->mem_ops is NULL, we request that at least one of the + * ->transfer_xxx() method be implemented. + */ + if (ctlr->mem_ops) { + if (!ctlr->mem_ops->exec_op) + return -EINVAL; + } else if (!ctlr->transfer && !ctlr->transfer_one && + !ctlr->transfer_one_message) { + return -EINVAL; + } + + return 0; +} + /** * spi_register_controller - register SPI master or slave controller * @ctlr: initialized master, originally from spi_alloc_master() or @@ -2096,6 +2123,14 @@ int spi_register_controller(struct spi_controller *ctlr) if (!dev) return -ENODEV; + /* + * Make sure all necessary hooks are implemented before registering + * the SPI controller. + */ + status = spi_controller_check_ops(ctlr); + if (status) + return status; + if (!spi_controller_is_slave(ctlr)) { status = of_spi_register_master(ctlr); if (status) @@ -2161,10 +2196,14 @@ int spi_register_controller(struct spi_controller *ctlr) spi_controller_is_slave(ctlr) ? "slave" : "master", dev_name(&ctlr->dev)); - /* If we're using a queued driver, start the queue */ - if (ctlr->transfer) + /* + * If we're using a queued driver, start the queue. Note that we don't + * need the queueing logic if the driver is only supporting high-level + * memory operations. + */ + if (ctlr->transfer) { dev_info(dev, "controller is unqueued, this is deprecated\n"); - else { + } else if (ctlr->transfer_one || ctlr->transfer_one_message) { status = spi_controller_initialize_queue(ctlr); if (status) { device_del(&ctlr->dev); @@ -2894,6 +2933,13 @@ static int __spi_async(struct spi_device *spi, struct spi_message *message) { struct spi_controller *ctlr = spi->controller; + /* + * Some controllers do not support doing regular SPI transfers. Return + * ENOTSUPP when this is the case. + */ + if (!ctlr->transfer) + return -ENOTSUPP; + message->spi = spi; SPI_STATISTICS_INCREMENT_FIELD(&ctlr->statistics, spi_async); @@ -3010,63 +3056,6 @@ int spi_async_locked(struct spi_device *spi, struct spi_message *message) } EXPORT_SYMBOL_GPL(spi_async_locked); - -int spi_flash_read(struct spi_device *spi, - struct spi_flash_read_message *msg) - -{ - struct spi_controller *master = spi->controller; - struct device *rx_dev = NULL; - int ret; - - if ((msg->opcode_nbits == SPI_NBITS_DUAL || - msg->addr_nbits == SPI_NBITS_DUAL) && - !(spi->mode & (SPI_TX_DUAL | SPI_TX_QUAD))) - return -EINVAL; - if ((msg->opcode_nbits == SPI_NBITS_QUAD || - msg->addr_nbits == SPI_NBITS_QUAD) && - !(spi->mode & SPI_TX_QUAD)) - return -EINVAL; - if (msg->data_nbits == SPI_NBITS_DUAL && - !(spi->mode & (SPI_RX_DUAL | SPI_RX_QUAD))) - return -EINVAL; - if (msg->data_nbits == SPI_NBITS_QUAD && - !(spi->mode & SPI_RX_QUAD)) - return -EINVAL; - - if (master->auto_runtime_pm) { - ret = pm_runtime_get_sync(master->dev.parent); - if (ret < 0) { - dev_err(&master->dev, "Failed to power device: %d\n", - ret); - return ret; - } - } - - mutex_lock(&master->bus_lock_mutex); - mutex_lock(&master->io_mutex); - if (master->dma_rx && master->spi_flash_can_dma(spi, msg)) { - rx_dev = master->dma_rx->device->dev; - ret = spi_map_buf(master, rx_dev, &msg->rx_sg, - msg->buf, msg->len, - DMA_FROM_DEVICE); - if (!ret) - msg->cur_msg_mapped = true; - } - ret = master->spi_flash_read(spi, msg); - if (msg->cur_msg_mapped) - spi_unmap_buf(master, rx_dev, &msg->rx_sg, - DMA_FROM_DEVICE); - mutex_unlock(&master->io_mutex); - mutex_unlock(&master->bus_lock_mutex); - - if (master->auto_runtime_pm) - pm_runtime_put(master->dev.parent); - - return ret; -} -EXPORT_SYMBOL_GPL(spi_flash_read); - /*-------------------------------------------------------------------------*/ /* Utility methods for SPI protocol drivers, layered on |