1 files changed, 214 insertions, 21 deletions

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index d0b28bba38be..ffc1a2ebc4ca 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -24,6 +24,8 @@
 #include <linux/device.h>
 #include <linux/init.h>
 #include <linux/cache.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
 #include <linux/mutex.h>
 #include <linux/of_device.h>
 #include <linux/of_irq.h>
@@ -255,13 +257,12 @@ EXPORT_SYMBOL_GPL(spi_bus_type);
 static int spi_drv_probe(struct device *dev)
 {
         const struct spi_driver         *sdrv = to_spi_driver(dev->driver);
-        struct spi_device               *spi = to_spi_device(dev);
         int ret;
 
-        acpi_dev_pm_attach(&spi->dev, true);
-        ret = sdrv->probe(spi);
+        acpi_dev_pm_attach(dev, true);
+        ret = sdrv->probe(to_spi_device(dev));
         if (ret)
-                acpi_dev_pm_detach(&spi->dev, true);
+                acpi_dev_pm_detach(dev, true);
 
         return ret;
 }
@@ -269,11 +270,10 @@ static int spi_drv_probe(struct device *dev)
 static int spi_drv_remove(struct device *dev)
 {
         const struct spi_driver         *sdrv = to_spi_driver(dev->driver);
-        struct spi_device               *spi = to_spi_device(dev);
         int ret;
 
-        ret = sdrv->remove(spi);
-        acpi_dev_pm_detach(&spi->dev, true);
+        ret = sdrv->remove(to_spi_device(dev));
+        acpi_dev_pm_detach(dev, true);
 
         return ret;
 }
@@ -580,6 +580,169 @@ static void spi_set_cs(struct spi_device *spi, bool enable)
                 spi->master->set_cs(spi, !enable);
 }
 
+static int spi_map_buf(struct spi_master *master, 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);
+        const int desc_len = vmalloced_buf ? PAGE_SIZE : master->max_dma_len;
+        const int sgs = DIV_ROUND_UP(len, desc_len);
+        struct page *vm_page;
+        void *sg_buf;
+        size_t min;
+        int i, ret;
+
+        ret = sg_alloc_table(sgt, sgs, GFP_KERNEL);
+        if (ret != 0)
+                return ret;
+
+        for (i = 0; i < sgs; i++) {
+                min = min_t(size_t, len, desc_len);
+
+                if (vmalloced_buf) {
+                        vm_page = vmalloc_to_page(buf);
+                        if (!vm_page) {
+                                sg_free_table(sgt);
+                                return -ENOMEM;
+                        }
+                        sg_buf = page_address(vm_page) +
+                                ((size_t)buf & ~PAGE_MASK);
+                } else {
+                        sg_buf = buf;
+                }
+
+                sg_set_buf(&sgt->sgl[i], sg_buf, min);
+
+                buf += min;
+                len -= min;
+        }
+
+        ret = dma_map_sg(dev, sgt->sgl, sgt->nents, dir);
+        if (ret < 0) {
+                sg_free_table(sgt);
+                return ret;
+        }
+
+        sgt->nents = ret;
+
+        return 0;
+}
+
+static void spi_unmap_buf(struct spi_master *master, 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);
+                sg_free_table(sgt);
+        }
+}
+
+static int spi_map_msg(struct spi_master *master, struct spi_message *msg)
+{
+        struct device *tx_dev, *rx_dev;
+        struct spi_transfer *xfer;
+        void *tmp;
+        unsigned int max_tx, max_rx;
+        int ret;
+
+        if (master->flags & (SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX)) {
+                max_tx = 0;
+                max_rx = 0;
+
+                list_for_each_entry(xfer, &msg->transfers, transfer_list) {
+                        if ((master->flags & SPI_MASTER_MUST_TX) &&
+                            !xfer->tx_buf)
+                                max_tx = max(xfer->len, max_tx);
+                        if ((master->flags & SPI_MASTER_MUST_RX) &&
+                            !xfer->rx_buf)
+                                max_rx = max(xfer->len, max_rx);
+                }
+
+                if (max_tx) {
+                        tmp = krealloc(master->dummy_tx, max_tx,
+                                       GFP_KERNEL | GFP_DMA);
+                        if (!tmp)
+                                return -ENOMEM;
+                        master->dummy_tx = tmp;
+                        memset(tmp, 0, max_tx);
+                }
+
+                if (max_rx) {
+                        tmp = krealloc(master->dummy_rx, max_rx,
+                                       GFP_KERNEL | GFP_DMA);
+                        if (!tmp)
+                                return -ENOMEM;
+                        master->dummy_rx = tmp;
+                }
+
+                if (max_tx || max_rx) {
+                        list_for_each_entry(xfer, &msg->transfers,
+                                            transfer_list) {
+                                if (!xfer->tx_buf)
+                                        xfer->tx_buf = master->dummy_tx;
+                                if (!xfer->rx_buf)
+                                        xfer->rx_buf = master->dummy_rx;
+                        }
+                }
+        }
+
+        if (!master->can_dma)
+                return 0;
+
+        tx_dev = &master->dma_tx->dev->device;
+        rx_dev = &master->dma_rx->dev->device;
+
+        list_for_each_entry(xfer, &msg->transfers, transfer_list) {
+                if (!master->can_dma(master, msg->spi, xfer))
+                        continue;
+
+                if (xfer->tx_buf != NULL) {
+                        ret = spi_map_buf(master, tx_dev, &xfer->tx_sg,
+                                          (void *)xfer->tx_buf, xfer->len,
+                                          DMA_TO_DEVICE);
+                        if (ret != 0)
+                                return ret;
+                }
+
+                if (xfer->rx_buf != NULL) {
+                        ret = spi_map_buf(master, rx_dev, &xfer->rx_sg,
+                                          xfer->rx_buf, xfer->len,
+                                          DMA_FROM_DEVICE);
+                        if (ret != 0) {
+                                spi_unmap_buf(master, tx_dev, &xfer->tx_sg,
+                                              DMA_TO_DEVICE);
+                                return ret;
+                        }
+                }
+        }
+
+        master->cur_msg_mapped = true;
+
+        return 0;
+}
+
+static int spi_unmap_msg(struct spi_master *master, struct spi_message *msg)
+{
+        struct spi_transfer *xfer;
+        struct device *tx_dev, *rx_dev;
+
+        if (!master->cur_msg_mapped || !master->can_dma)
+                return 0;
+
+        tx_dev = &master->dma_tx->dev->device;
+        rx_dev = &master->dma_rx->dev->device;
+
+        list_for_each_entry(xfer, &msg->transfers, transfer_list) {
+                if (!master->can_dma(master, msg->spi, xfer))
+                        continue;
+
+                spi_unmap_buf(master, rx_dev, &xfer->rx_sg, DMA_FROM_DEVICE);
+                spi_unmap_buf(master, tx_dev, &xfer->tx_sg, DMA_TO_DEVICE);
+        }
+
+        return 0;
+}
+
 /*
  * spi_transfer_one_message - Default implementation of transfer_one_message()
  *
@@ -591,7 +754,6 @@ static int spi_transfer_one_message(struct spi_master *master,
                                     struct spi_message *msg)
 {
         struct spi_transfer *xfer;
-        bool cur_cs = true;
         bool keep_cs = false;
         int ret = 0;
 
@@ -627,8 +789,9 @@ static int spi_transfer_one_message(struct spi_master *master,
                                          &msg->transfers)) {
                                 keep_cs = true;
                         } else {
-                                cur_cs = !cur_cs;
-                                spi_set_cs(msg->spi, cur_cs);
+                                spi_set_cs(msg->spi, false);
+                                udelay(10);
+                                spi_set_cs(msg->spi, true);
                         }
                 }
 
@@ -686,6 +849,10 @@ static void spi_pump_messages(struct kthread_work *work)
                 }
                 master->busy = false;
                 spin_unlock_irqrestore(&master->queue_lock, flags);
+                kfree(master->dummy_rx);
+                master->dummy_rx = NULL;
+                kfree(master->dummy_tx);
+                master->dummy_tx = NULL;
                 if (master->unprepare_transfer_hardware &&
                     master->unprepare_transfer_hardware(master))
                         dev_err(&master->dev,
@@ -752,6 +919,13 @@ static void spi_pump_messages(struct kthread_work *work)
                 master->cur_msg_prepared = true;
         }
 
+        ret = spi_map_msg(master, master->cur_msg);
+        if (ret) {
+                master->cur_msg->status = ret;
+                spi_finalize_current_message(master);
+                return;
+        }
+
         ret = master->transfer_one_message(master, master->cur_msg);
         if (ret) {
                 dev_err(&master->dev,
@@ -839,6 +1013,8 @@ void spi_finalize_current_message(struct spi_master *master)
         queue_kthread_work(&master->kworker, &master->pump_messages);
         spin_unlock_irqrestore(&master->queue_lock, flags);
 
+        spi_unmap_msg(master, mesg);
+
         if (master->cur_msg_prepared && master->unprepare_message) {
                 ret = master->unprepare_message(master, mesg);
                 if (ret) {
@@ -892,7 +1068,7 @@ static int spi_stop_queue(struct spi_master *master)
          */
         while ((!list_empty(&master->queue) || master->busy) && limit--) {
                 spin_unlock_irqrestore(&master->queue_lock, flags);
-                msleep(10);
+                usleep_range(10000, 11000);
                 spin_lock_irqsave(&master->queue_lock, flags);
         }
 
@@ -1372,6 +1548,8 @@ int spi_register_master(struct spi_master *master)
         mutex_init(&master->bus_lock_mutex);
         master->bus_lock_flag = 0;
         init_completion(&master->xfer_completion);
+        if (!master->max_dma_len)
+                master->max_dma_len = INT_MAX;
 
         /* register the device, then userspace will see it.
          * registration fails if the bus ID is in use.
@@ -1597,6 +1775,9 @@ int spi_setup(struct spi_device *spi)
         if (!spi->bits_per_word)
                 spi->bits_per_word = 8;
 
+        if (!spi->max_speed_hz)
+                spi->max_speed_hz = spi->master->max_speed_hz;
+
         if (spi->master->setup)
                 status = spi->master->setup(spi);
 
@@ -1617,11 +1798,10 @@ static int __spi_validate(struct spi_device *spi, struct spi_message *message)
 {
         struct spi_master *master = spi->master;
         struct spi_transfer *xfer;
+        int w_size;
 
         if (list_empty(&message->transfers))
                 return -EINVAL;
-        if (!message->complete)
-                return -EINVAL;
 
         /* Half-duplex links include original MicroWire, and ones with
          * only one data pin like SPI_3WIRE (switches direction) or where
@@ -1652,12 +1832,13 @@ static int __spi_validate(struct spi_device *spi, struct spi_message *message)
                 message->frame_length += xfer->len;
                 if (!xfer->bits_per_word)
                         xfer->bits_per_word = spi->bits_per_word;
-                if (!xfer->speed_hz) {
+
+                if (!xfer->speed_hz)
                         xfer->speed_hz = spi->max_speed_hz;
-                        if (master->max_speed_hz &&
-                            xfer->speed_hz > master->max_speed_hz)
-                                xfer->speed_hz = master->max_speed_hz;
-                }
+
+                if (master->max_speed_hz &&
+                    xfer->speed_hz > master->max_speed_hz)
+                        xfer->speed_hz = master->max_speed_hz;
 
                 if (master->bits_per_word_mask) {
                         /* Only 32 bits fit in the mask */
@@ -1668,12 +1849,24 @@ static int __spi_validate(struct spi_device *spi, struct spi_message *message)
                                 return -EINVAL;
                 }
 
+                /*
+                 * SPI transfer length should be multiple of SPI word size
+                 * where SPI word size should be power-of-two multiple
+                 */
+                if (xfer->bits_per_word <= 8)
+                        w_size = 1;
+                else if (xfer->bits_per_word <= 16)
+                        w_size = 2;
+                else
+                        w_size = 4;
+
+                /* No partial transfers accepted */
+                if (xfer->len % w_size)
+                        return -EINVAL;
+
                 if (xfer->speed_hz && master->min_speed_hz &&
                     xfer->speed_hz < master->min_speed_hz)
                         return -EINVAL;
-                if (xfer->speed_hz && master->max_speed_hz &&
-                    xfer->speed_hz > master->max_speed_hz)
-                        return -EINVAL;
 
                 if (xfer->tx_buf && !xfer->tx_nbits)
                         xfer->tx_nbits = SPI_NBITS_SINGLE;