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path: root/drivers/spi/spi.c
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Diffstat (limited to 'drivers/spi/spi.c')
-rw-r--r--drivers/spi/spi.c156
1 files changed, 73 insertions, 83 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 7b213faa0a2b..efc624f9e490 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)
@@ -356,11 +359,12 @@ static int spi_drv_probe(struct device *dev)
}
ret = dev_pm_domain_attach(dev, true);
- if (ret != -EPROBE_DEFER) {
- ret = sdrv->probe(spi);
- if (ret)
- dev_pm_domain_detach(dev, true);
- }
+ if (ret)
+ return ret;
+
+ ret = sdrv->probe(spi);
+ if (ret)
+ dev_pm_domain_detach(dev, true);
return ret;
}
@@ -740,9 +744,9 @@ 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 +825,8 @@ 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 +911,6 @@ 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 +1213,7 @@ 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 +1525,22 @@ 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 +2071,26 @@ 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 +2124,14 @@ 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 +2197,14 @@ 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 +2934,13 @@ 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 +3057,6 @@ 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