]> git.karo-electronics.de Git - karo-tx-linux.git/blobdiff - drivers/spi/spi.c
Merge remote-tracking branch 'spi/for-next'
[karo-tx-linux.git] / drivers / spi / spi.c
index 740f9ddda227d55f15042e1e7a8d2cadb58aae71..927998aa5e71e711177a3adbf7cfe94ed020a85b 100644 (file)
@@ -39,6 +39,9 @@
 #include <linux/ioport.h>
 #include <linux/acpi.h>
 
+#define CREATE_TRACE_POINTS
+#include <trace/events/spi.h>
+
 static void spidev_release(struct device *dev)
 {
        struct spi_device       *spi = to_spi_device(dev);
@@ -58,11 +61,13 @@ modalias_show(struct device *dev, struct device_attribute *a, char *buf)
 
        return sprintf(buf, "%s%s\n", SPI_MODULE_PREFIX, spi->modalias);
 }
+static DEVICE_ATTR_RO(modalias);
 
-static struct device_attribute spi_dev_attrs[] = {
-       __ATTR_RO(modalias),
-       __ATTR_NULL,
+static struct attribute *spi_dev_attrs[] = {
+       &dev_attr_modalias.attr,
+       NULL,
 };
+ATTRIBUTE_GROUPS(spi_dev);
 
 /* modalias support makes "modprobe $MODALIAS" new-style hotplug work,
  * and the sysfs version makes coldplug work too.
@@ -229,7 +234,7 @@ static const struct dev_pm_ops spi_pm = {
 
 struct bus_type spi_bus_type = {
        .name           = "spi",
-       .dev_attrs      = spi_dev_attrs,
+       .dev_groups     = spi_dev_groups,
        .match          = spi_match_device,
        .uevent         = spi_uevent,
        .pm             = &spi_pm,
@@ -335,7 +340,7 @@ struct spi_device *spi_alloc_device(struct spi_master *master)
        if (!spi_master_get(master))
                return NULL;
 
-       spi = kzalloc(sizeof *spi, GFP_KERNEL);
+       spi = kzalloc(sizeof(*spi), GFP_KERNEL);
        if (!spi) {
                dev_err(dev, "cannot alloc spi_device\n");
                spi_master_put(master);
@@ -535,6 +540,95 @@ int spi_register_board_info(struct spi_board_info const *info, unsigned n)
 
 /*-------------------------------------------------------------------------*/
 
+static void spi_set_cs(struct spi_device *spi, bool enable)
+{
+       if (spi->mode & SPI_CS_HIGH)
+               enable = !enable;
+
+       if (spi->cs_gpio >= 0)
+               gpio_set_value(spi->cs_gpio, !enable);
+       else if (spi->master->set_cs)
+               spi->master->set_cs(spi, !enable);
+}
+
+/*
+ * spi_transfer_one_message - Default implementation of transfer_one_message()
+ *
+ * This is a standard implementation of transfer_one_message() for
+ * drivers which impelment a transfer_one() operation.  It provides
+ * standard handling of delays and chip select management.
+ */
+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;
+
+       spi_set_cs(msg->spi, true);
+
+       list_for_each_entry(xfer, &msg->transfers, transfer_list) {
+               trace_spi_transfer_start(msg, xfer);
+
+               INIT_COMPLETION(master->xfer_completion);
+
+               ret = master->transfer_one(master, msg->spi, xfer);
+               if (ret < 0) {
+                       dev_err(&msg->spi->dev,
+                               "SPI transfer failed: %d\n", ret);
+                       goto out;
+               }
+
+               if (ret > 0)
+                       wait_for_completion(&master->xfer_completion);
+
+               trace_spi_transfer_stop(msg, xfer);
+
+               if (msg->status != -EINPROGRESS)
+                       goto out;
+
+               if (xfer->delay_usecs)
+                       udelay(xfer->delay_usecs);
+
+               if (xfer->cs_change) {
+                       if (list_is_last(&xfer->transfer_list,
+                                        &msg->transfers)) {
+                               keep_cs = true;
+                       } else {
+                               cur_cs = !cur_cs;
+                               spi_set_cs(msg->spi, cur_cs);
+                       }
+               }
+
+               msg->actual_length += xfer->len;
+       }
+
+out:
+       if (ret != 0 || !keep_cs)
+               spi_set_cs(msg->spi, false);
+
+       if (msg->status == -EINPROGRESS)
+               msg->status = ret;
+
+       spi_finalize_current_message(master);
+
+       return ret;
+}
+
+/**
+ * spi_finalize_current_transfer - report completion of a transfer
+ *
+ * Called by SPI drivers using the core transfer_one_message()
+ * implementation to notify it that the current interrupt driven
+ * transfer has finised and the next one may be scheduled.
+ */
+void spi_finalize_current_transfer(struct spi_master *master)
+{
+       complete(&master->xfer_completion);
+}
+EXPORT_SYMBOL_GPL(spi_finalize_current_transfer);
+
 /**
  * spi_pump_messages - kthread work function which processes spi message queue
  * @work: pointer to kthread work struct contained in the master struct
@@ -569,6 +663,7 @@ static void spi_pump_messages(struct kthread_work *work)
                        pm_runtime_mark_last_busy(master->dev.parent);
                        pm_runtime_put_autosuspend(master->dev.parent);
                }
+               trace_spi_master_idle(master);
                return;
        }
 
@@ -597,6 +692,9 @@ static void spi_pump_messages(struct kthread_work *work)
                }
        }
 
+       if (!was_busy)
+               trace_spi_master_busy(master);
+
        if (!was_busy && master->prepare_transfer_hardware) {
                ret = master->prepare_transfer_hardware(master);
                if (ret) {
@@ -609,6 +707,20 @@ static void spi_pump_messages(struct kthread_work *work)
                }
        }
 
+       trace_spi_message_start(master->cur_msg);
+
+       if (master->prepare_message) {
+               ret = master->prepare_message(master, master->cur_msg);
+               if (ret) {
+                       dev_err(&master->dev,
+                               "failed to prepare message: %d\n", ret);
+                       master->cur_msg->status = ret;
+                       spi_finalize_current_message(master);
+                       return;
+               }
+               master->cur_msg_prepared = true;
+       }
+
        ret = master->transfer_one_message(master, master->cur_msg);
        if (ret) {
                dev_err(&master->dev,
@@ -690,6 +802,7 @@ void spi_finalize_current_message(struct spi_master *master)
 {
        struct spi_message *mesg;
        unsigned long flags;
+       int ret;
 
        spin_lock_irqsave(&master->queue_lock, flags);
        mesg = master->cur_msg;
@@ -698,9 +811,20 @@ void spi_finalize_current_message(struct spi_master *master)
        queue_kthread_work(&master->kworker, &master->pump_messages);
        spin_unlock_irqrestore(&master->queue_lock, flags);
 
+       if (master->cur_msg_prepared && master->unprepare_message) {
+               ret = master->unprepare_message(master, mesg);
+               if (ret) {
+                       dev_err(&master->dev,
+                               "failed to unprepare message: %d\n", ret);
+               }
+       }
+       master->cur_msg_prepared = false;
+
        mesg->state = NULL;
        if (mesg->complete)
                mesg->complete(mesg->context);
+
+       trace_spi_message_done(mesg);
 }
 EXPORT_SYMBOL_GPL(spi_finalize_current_message);
 
@@ -815,6 +939,8 @@ static int spi_master_initialize_queue(struct spi_master *master)
 
        master->queued = true;
        master->transfer = spi_queued_transfer;
+       if (!master->transfer_one_message)
+               master->transfer_one_message = spi_transfer_one_message;
 
        /* Initialize and start queue */
        ret = spi_init_queue(master);
@@ -850,10 +976,8 @@ static void of_register_spi_devices(struct spi_master *master)
 {
        struct spi_device *spi;
        struct device_node *nc;
-       const __be32 *prop;
-       char modalias[SPI_NAME_SIZE + 4];
        int rc;
-       int len;
+       u32 value;
 
        if (!master->dev.of_node)
                return;
@@ -878,14 +1002,14 @@ static void of_register_spi_devices(struct spi_master *master)
                }
 
                /* Device address */
-               prop = of_get_property(nc, "reg", &len);
-               if (!prop || len < sizeof(*prop)) {
-                       dev_err(&master->dev, "%s has no 'reg' property\n",
-                               nc->full_name);
+               rc = of_property_read_u32(nc, "reg", &value);
+               if (rc) {
+                       dev_err(&master->dev, "%s has no valid 'reg' property (%d)\n",
+                               nc->full_name, rc);
                        spi_dev_put(spi);
                        continue;
                }
-               spi->chip_select = be32_to_cpup(prop);
+               spi->chip_select = value;
 
                /* Mode (clock phase/polarity/etc.) */
                if (of_find_property(nc, "spi-cpha", NULL))
@@ -898,55 +1022,53 @@ static void of_register_spi_devices(struct spi_master *master)
                        spi->mode |= SPI_3WIRE;
 
                /* Device DUAL/QUAD mode */
-               prop = of_get_property(nc, "spi-tx-bus-width", &len);
-               if (prop && len == sizeof(*prop)) {
-                       switch (be32_to_cpup(prop)) {
-                       case SPI_NBITS_SINGLE:
+               if (!of_property_read_u32(nc, "spi-tx-bus-width", &value)) {
+                       switch (value) {
+                       case 1:
                                break;
-                       case SPI_NBITS_DUAL:
+                       case 2:
                                spi->mode |= SPI_TX_DUAL;
                                break;
-                       case SPI_NBITS_QUAD:
+                       case 4:
                                spi->mode |= SPI_TX_QUAD;
                                break;
                        default:
                                dev_err(&master->dev,
                                        "spi-tx-bus-width %d not supported\n",
-                                       be32_to_cpup(prop));
+                                       value);
                                spi_dev_put(spi);
                                continue;
                        }
                }
 
-               prop = of_get_property(nc, "spi-rx-bus-width", &len);
-               if (prop && len == sizeof(*prop)) {
-                       switch (be32_to_cpup(prop)) {
-                       case SPI_NBITS_SINGLE:
+               if (!of_property_read_u32(nc, "spi-rx-bus-width", &value)) {
+                       switch (value) {
+                       case 1:
                                break;
-                       case SPI_NBITS_DUAL:
+                       case 2:
                                spi->mode |= SPI_RX_DUAL;
                                break;
-                       case SPI_NBITS_QUAD:
+                       case 4:
                                spi->mode |= SPI_RX_QUAD;
                                break;
                        default:
                                dev_err(&master->dev,
                                        "spi-rx-bus-width %d not supported\n",
-                                       be32_to_cpup(prop));
+                                       value);
                                spi_dev_put(spi);
                                continue;
                        }
                }
 
                /* Device speed */
-               prop = of_get_property(nc, "spi-max-frequency", &len);
-               if (!prop || len < sizeof(*prop)) {
-                       dev_err(&master->dev, "%s has no 'spi-max-frequency' property\n",
-                               nc->full_name);
+               rc = of_property_read_u32(nc, "spi-max-frequency", &value);
+               if (rc) {
+                       dev_err(&master->dev, "%s has no valid 'spi-max-frequency' property (%d)\n",
+                               nc->full_name, rc);
                        spi_dev_put(spi);
                        continue;
                }
-               spi->max_speed_hz = be32_to_cpup(prop);
+               spi->max_speed_hz = value;
 
                /* IRQ */
                spi->irq = irq_of_parse_and_map(nc, 0);
@@ -956,9 +1078,7 @@ static void of_register_spi_devices(struct spi_master *master)
                spi->dev.of_node = nc;
 
                /* Register the new device */
-               snprintf(modalias, sizeof(modalias), "%s%s", SPI_MODULE_PREFIX,
-                        spi->modalias);
-               request_module(modalias);
+               request_module("%s%s", SPI_MODULE_PREFIX, spi->modalias);
                rc = spi_add_device(spi);
                if (rc) {
                        dev_err(&master->dev, "spi_device register error %s\n",
@@ -1038,7 +1158,7 @@ static acpi_status acpi_spi_add_device(acpi_handle handle, u32 level,
        }
 
        adev->power.flags.ignore_parent = true;
-       strlcpy(spi->modalias, dev_name(&adev->dev), sizeof(spi->modalias));
+       strlcpy(spi->modalias, acpi_device_hid(adev), sizeof(spi->modalias));
        if (spi_add_device(spi)) {
                adev->power.flags.ignore_parent = false;
                dev_err(&master->dev, "failed to add SPI device %s from ACPI\n",
@@ -1111,7 +1231,7 @@ struct spi_master *spi_alloc_master(struct device *dev, unsigned size)
        if (!dev)
                return NULL;
 
-       master = kzalloc(size + sizeof *master, GFP_KERNEL);
+       master = kzalloc(size + sizeof(*master), GFP_KERNEL);
        if (!master)
                return NULL;
 
@@ -1136,7 +1256,7 @@ static int of_spi_register_master(struct spi_master *master)
                return 0;
 
        nb = of_gpio_named_count(np, "cs-gpios");
-       master->num_chipselect = max(nb, (int)master->num_chipselect);
+       master->num_chipselect = max_t(int, nb, master->num_chipselect);
 
        /* Return error only for an incorrectly formed cs-gpios property */
        if (nb == 0 || nb == -ENOENT)
@@ -1223,6 +1343,7 @@ int spi_register_master(struct spi_master *master)
        spin_lock_init(&master->bus_lock_spinlock);
        mutex_init(&master->bus_lock_mutex);
        master->bus_lock_flag = 0;
+       init_completion(&master->xfer_completion);
 
        /* register the device, then userspace will see it.
         * registration fails if the bus ID is in use.
@@ -1259,6 +1380,41 @@ done:
 }
 EXPORT_SYMBOL_GPL(spi_register_master);
 
+static void devm_spi_unregister(struct device *dev, void *res)
+{
+       spi_unregister_master(*(struct spi_master **)res);
+}
+
+/**
+ * dev_spi_register_master - register managed SPI master controller
+ * @dev:    device managing SPI master
+ * @master: initialized master, originally from spi_alloc_master()
+ * Context: can sleep
+ *
+ * Register a SPI device as with spi_register_master() which will
+ * automatically be unregister
+ */
+int devm_spi_register_master(struct device *dev, struct spi_master *master)
+{
+       struct spi_master **ptr;
+       int ret;
+
+       ptr = devres_alloc(devm_spi_unregister, sizeof(*ptr), GFP_KERNEL);
+       if (!ptr)
+               return -ENOMEM;
+
+       ret = spi_register_master(master);
+       if (ret != 0) {
+               *ptr = master;
+               devres_add(dev, ptr);
+       } else {
+               devres_free(ptr);
+       }
+
+       return ret;
+}
+EXPORT_SYMBOL_GPL(devm_spi_register_master);
+
 static int __unregister(struct device *dev, void *null)
 {
        spi_unregister_device(to_spi_device(dev));
@@ -1416,8 +1572,7 @@ int spi_setup(struct spi_device *spi)
        if (spi->master->setup)
                status = spi->master->setup(spi);
 
-       dev_dbg(&spi->dev, "setup mode %d, %s%s%s%s"
-                               "%u bits/w, %u Hz max --> %d\n",
+       dev_dbg(&spi->dev, "setup mode %d, %s%s%s%s%u bits/w, %u Hz max --> %d\n",
                        (int) (spi->mode & (SPI_CPOL | SPI_CPHA)),
                        (spi->mode & SPI_CS_HIGH) ? "cs_high, " : "",
                        (spi->mode & SPI_LSB_FIRST) ? "lsb, " : "",
@@ -1435,6 +1590,10 @@ static int __spi_async(struct spi_device *spi, struct spi_message *message)
        struct spi_master *master = spi->master;
        struct spi_transfer *xfer;
 
+       message->spi = spi;
+
+       trace_spi_message_submit(message);
+
        if (list_empty(&message->transfers))
                return -EINVAL;
        if (!message->complete)
@@ -1534,7 +1693,6 @@ static int __spi_async(struct spi_device *spi, struct spi_message *message)
                }
        }
 
-       message->spi = spi;
        message->status = -EINPROGRESS;
        return master->transfer(spi, message);
 }
@@ -1776,7 +1934,7 @@ int spi_bus_unlock(struct spi_master *master)
 EXPORT_SYMBOL_GPL(spi_bus_unlock);
 
 /* portable code must never pass more than 32 bytes */
-#define        SPI_BUFSIZ      max(32,SMP_CACHE_BYTES)
+#define        SPI_BUFSIZ      max(32, SMP_CACHE_BYTES)
 
 static u8      *buf;
 
@@ -1825,7 +1983,7 @@ int spi_write_then_read(struct spi_device *spi,
        }
 
        spi_message_init(&message);
-       memset(x, 0, sizeof x);
+       memset(x, 0, sizeof(x));
        if (n_tx) {
                x[0].len = n_tx;
                spi_message_add_tail(&x[0], &message);