aboutsummaryrefslogtreecommitdiff
path: root/drivers/spi/spi.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/spi/spi.c')
-rw-r--r--drivers/spi/spi.c291
1 files changed, 162 insertions, 129 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index d96082dc3340..c4dd1200fe99 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -18,7 +18,6 @@
#include <linux/mod_devicetable.h>
#include <linux/spi/spi.h>
#include <linux/spi/spi-mem.h>
-#include <linux/of_gpio.h>
#include <linux/gpio/consumer.h>
#include <linux/pm_runtime.h>
#include <linux/pm_domain.h>
@@ -144,7 +143,7 @@ static ssize_t spi_statistics_##name##_show(struct spi_statistics *stat, \
unsigned long flags; \
ssize_t len; \
spin_lock_irqsave(&stat->lock, flags); \
- len = sprintf(buf, format_string, stat->field); \
+ len = sysfs_emit(buf, format_string "\n", stat->field); \
spin_unlock_irqrestore(&stat->lock, flags); \
return len; \
} \
@@ -404,15 +403,8 @@ static void spi_remove(struct device *dev)
{
const struct spi_driver *sdrv = to_spi_driver(dev->driver);
- if (sdrv->remove) {
- int ret;
-
- ret = sdrv->remove(to_spi_device(dev));
- if (ret)
- dev_warn(dev,
- "Failed to unbind driver (%pe), ignoring\n",
- ERR_PTR(ret));
- }
+ if (sdrv->remove)
+ sdrv->remove(to_spi_device(dev));
dev_pm_domain_detach(dev, true);
}
@@ -532,7 +524,7 @@ static DEFINE_MUTEX(board_lock);
*
* Return: a pointer to the new device, or NULL.
*/
-static struct spi_device *spi_alloc_device(struct spi_controller *ctlr)
+struct spi_device *spi_alloc_device(struct spi_controller *ctlr)
{
struct spi_device *spi;
@@ -549,7 +541,6 @@ static struct spi_device *spi_alloc_device(struct spi_controller *ctlr)
spi->dev.parent = &ctlr->dev;
spi->dev.bus = &spi_bus_type;
spi->dev.release = spidev_release;
- spi->cs_gpio = -ENOENT;
spi->mode = ctlr->buswidth_override_bits;
spin_lock_init(&spi->statistics.lock);
@@ -557,6 +548,7 @@ static struct spi_device *spi_alloc_device(struct spi_controller *ctlr)
device_initialize(&spi->dev);
return spi;
}
+EXPORT_SYMBOL_GPL(spi_alloc_device);
static void spi_dev_set_name(struct spi_device *spi)
{
@@ -612,11 +604,8 @@ static int __spi_add_device(struct spi_device *spi)
return -ENODEV;
}
- /* Descriptors take precedence */
if (ctlr->cs_gpiods)
spi->cs_gpiod = ctlr->cs_gpiods[spi->chip_select];
- else if (ctlr->cs_gpios)
- spi->cs_gpio = ctlr->cs_gpios[spi->chip_select];
/*
* Drivers may modify this initial i/o setup, but will
@@ -652,7 +641,7 @@ static int __spi_add_device(struct spi_device *spi)
*
* Return: 0 on success; negative errno on failure
*/
-static int spi_add_device(struct spi_device *spi)
+int spi_add_device(struct spi_device *spi)
{
struct spi_controller *ctlr = spi->controller;
struct device *dev = ctlr->dev.parent;
@@ -673,6 +662,7 @@ static int spi_add_device(struct spi_device *spi)
mutex_unlock(&ctlr->add_lock);
return status;
}
+EXPORT_SYMBOL_GPL(spi_add_device);
static int spi_add_device_locked(struct spi_device *spi)
{
@@ -936,48 +926,40 @@ static void spi_set_cs(struct spi_device *spi, bool enable, bool force)
* Avoid calling into the driver (or doing delays) if the chip select
* isn't actually changing from the last time this was called.
*/
- if (!force && (spi->controller->last_cs_enable == enable) &&
+ if (!force && ((enable && spi->controller->last_cs == spi->chip_select) ||
+ (!enable && spi->controller->last_cs != spi->chip_select)) &&
(spi->controller->last_cs_mode_high == (spi->mode & SPI_CS_HIGH)))
return;
trace_spi_set_cs(spi, activate);
- spi->controller->last_cs_enable = enable;
+ spi->controller->last_cs = enable ? spi->chip_select : -1;
spi->controller->last_cs_mode_high = spi->mode & SPI_CS_HIGH;
- if ((spi->cs_gpiod || gpio_is_valid(spi->cs_gpio) ||
- !spi->controller->set_cs_timing) && !activate) {
+ if ((spi->cs_gpiod || !spi->controller->set_cs_timing) && !activate) {
spi_delay_exec(&spi->cs_hold, NULL);
}
if (spi->mode & SPI_CS_HIGH)
enable = !enable;
- if (spi->cs_gpiod || gpio_is_valid(spi->cs_gpio)) {
+ if (spi->cs_gpiod) {
if (!(spi->mode & SPI_NO_CS)) {
- if (spi->cs_gpiod) {
- /*
- * Historically ACPI has no means of the GPIO polarity and
- * thus the SPISerialBus() resource defines it on the per-chip
- * basis. In order to avoid a chain of negations, the GPIO
- * polarity is considered being Active High. Even for the cases
- * when _DSD() is involved (in the updated versions of ACPI)
- * the GPIO CS polarity must be defined Active High to avoid
- * ambiguity. That's why we use enable, that takes SPI_CS_HIGH
- * into account.
- */
- if (has_acpi_companion(&spi->dev))
- gpiod_set_value_cansleep(spi->cs_gpiod, !enable);
- else
- /* Polarity handled by GPIO library */
- gpiod_set_value_cansleep(spi->cs_gpiod, activate);
- } else {
- /*
- * Invert the enable line, as active low is
- * default for SPI.
- */
- gpio_set_value_cansleep(spi->cs_gpio, !enable);
- }
+ /*
+ * Historically ACPI has no means of the GPIO polarity and
+ * thus the SPISerialBus() resource defines it on the per-chip
+ * basis. In order to avoid a chain of negations, the GPIO
+ * polarity is considered being Active High. Even for the cases
+ * when _DSD() is involved (in the updated versions of ACPI)
+ * the GPIO CS polarity must be defined Active High to avoid
+ * ambiguity. That's why we use enable, that takes SPI_CS_HIGH
+ * into account.
+ */
+ if (has_acpi_companion(&spi->dev))
+ gpiod_set_value_cansleep(spi->cs_gpiod, !enable);
+ else
+ /* Polarity handled by GPIO library */
+ gpiod_set_value_cansleep(spi->cs_gpiod, activate);
}
/* Some SPI masters need both GPIO CS & slave_select */
if ((spi->controller->flags & SPI_MASTER_GPIO_SS) &&
@@ -987,8 +969,7 @@ static void spi_set_cs(struct spi_device *spi, bool enable, bool force)
spi->controller->set_cs(spi, !enable);
}
- if (spi->cs_gpiod || gpio_is_valid(spi->cs_gpio) ||
- !spi->controller->set_cs_timing) {
+ if (spi->cs_gpiod || !spi->controller->set_cs_timing) {
if (activate)
spi_delay_exec(&spi->cs_setup, NULL);
else
@@ -1019,10 +1000,10 @@ int spi_map_buf(struct spi_controller *ctlr, struct device *dev,
int i, ret;
if (vmalloced_buf || kmap_buf) {
- desc_len = min_t(unsigned int, max_seg_size, PAGE_SIZE);
+ desc_len = min_t(unsigned long, max_seg_size, PAGE_SIZE);
sgs = DIV_ROUND_UP(len + offset_in_page(buf), desc_len);
} else if (virt_addr_valid(buf)) {
- desc_len = min_t(unsigned int, max_seg_size, ctlr->max_dma_len);
+ desc_len = min_t(size_t, max_seg_size, ctlr->max_dma_len);
sgs = DIV_ROUND_UP(len, desc_len);
} else {
return -EINVAL;
@@ -2318,8 +2299,50 @@ struct acpi_spi_lookup {
int irq;
u8 bits_per_word;
u8 chip_select;
+ int n;
+ int index;
};
+static int acpi_spi_count(struct acpi_resource *ares, void *data)
+{
+ struct acpi_resource_spi_serialbus *sb;
+ int *count = data;
+
+ if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
+ return 1;
+
+ sb = &ares->data.spi_serial_bus;
+ if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_SPI)
+ return 1;
+
+ *count = *count + 1;
+
+ return 1;
+}
+
+/**
+ * acpi_spi_count_resources - Count the number of SpiSerialBus resources
+ * @adev: ACPI device
+ *
+ * Returns the number of SpiSerialBus resources in the ACPI-device's
+ * resource-list; or a negative error code.
+ */
+int acpi_spi_count_resources(struct acpi_device *adev)
+{
+ LIST_HEAD(r);
+ int count = 0;
+ int ret;
+
+ ret = acpi_dev_get_resources(adev, &r, acpi_spi_count, &count);
+ if (ret < 0)
+ return ret;
+
+ acpi_dev_free_resource_list(&r);
+
+ return count;
+}
+EXPORT_SYMBOL_GPL(acpi_spi_count_resources);
+
static void acpi_spi_parse_apple_properties(struct acpi_device *dev,
struct acpi_spi_lookup *lookup)
{
@@ -2349,6 +2372,8 @@ static void acpi_spi_parse_apple_properties(struct acpi_device *dev,
lookup->mode |= SPI_CPHA;
}
+static struct spi_controller *acpi_spi_find_controller_by_adev(struct acpi_device *adev);
+
static int acpi_spi_add_resource(struct acpi_resource *ares, void *data)
{
struct acpi_spi_lookup *lookup = data;
@@ -2362,14 +2387,35 @@ static int acpi_spi_add_resource(struct acpi_resource *ares, void *data)
sb = &ares->data.spi_serial_bus;
if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_SPI) {
+ if (lookup->index != -1 && lookup->n++ != lookup->index)
+ return 1;
+
+ if (lookup->index == -1 && !ctlr)
+ return -ENODEV;
+
status = acpi_get_handle(NULL,
sb->resource_source.string_ptr,
&parent_handle);
- if (ACPI_FAILURE(status) ||
- ACPI_HANDLE(ctlr->dev.parent) != parent_handle)
+ if (ACPI_FAILURE(status))
return -ENODEV;
+ if (ctlr) {
+ if (ACPI_HANDLE(ctlr->dev.parent) != parent_handle)
+ return -ENODEV;
+ } else {
+ struct acpi_device *adev;
+
+ if (acpi_bus_get_device(parent_handle, &adev))
+ return -ENODEV;
+
+ ctlr = acpi_spi_find_controller_by_adev(adev);
+ if (!ctlr)
+ return -ENODEV;
+
+ lookup->ctlr = ctlr;
+ }
+
/*
* ACPI DeviceSelection numbering is handled by the
* host controller driver in Windows and can vary
@@ -2408,8 +2454,25 @@ static int acpi_spi_add_resource(struct acpi_resource *ares, void *data)
return 1;
}
-static acpi_status acpi_register_spi_device(struct spi_controller *ctlr,
- struct acpi_device *adev)
+/**
+ * acpi_spi_device_alloc - Allocate a spi device, and fill it in with ACPI information
+ * @ctlr: controller to which the spi device belongs
+ * @adev: ACPI Device for the spi device
+ * @index: Index of the spi resource inside the ACPI Node
+ *
+ * This should be used to allocate a new spi device from and ACPI Node.
+ * The caller is responsible for calling spi_add_device to register the spi device.
+ *
+ * If ctlr is set to NULL, the Controller for the spi device will be looked up
+ * using the resource.
+ * If index is set to -1, index is not used.
+ * Note: If index is -1, ctlr must be set.
+ *
+ * Return: a pointer to the new device, or ERR_PTR on error.
+ */
+struct spi_device *acpi_spi_device_alloc(struct spi_controller *ctlr,
+ struct acpi_device *adev,
+ int index)
{
acpi_handle parent_handle = NULL;
struct list_head resource_list;
@@ -2417,12 +2480,13 @@ static acpi_status acpi_register_spi_device(struct spi_controller *ctlr,
struct spi_device *spi;
int ret;
- if (acpi_bus_get_status(adev) || !adev->status.present ||
- acpi_device_enumerated(adev))
- return AE_OK;
+ if (!ctlr && index == -1)
+ return ERR_PTR(-EINVAL);
lookup.ctlr = ctlr;
lookup.irq = -1;
+ lookup.index = index;
+ lookup.n = 0;
INIT_LIST_HEAD(&resource_list);
ret = acpi_dev_get_resources(adev, &resource_list,
@@ -2431,26 +2495,25 @@ static acpi_status acpi_register_spi_device(struct spi_controller *ctlr,
if (ret < 0)
/* found SPI in _CRS but it points to another controller */
- return AE_OK;
+ return ERR_PTR(-ENODEV);
if (!lookup.max_speed_hz &&
ACPI_SUCCESS(acpi_get_parent(adev->handle, &parent_handle)) &&
- ACPI_HANDLE(ctlr->dev.parent) == parent_handle) {
+ ACPI_HANDLE(lookup.ctlr->dev.parent) == parent_handle) {
/* Apple does not use _CRS but nested devices for SPI slaves */
acpi_spi_parse_apple_properties(adev, &lookup);
}
if (!lookup.max_speed_hz)
- return AE_OK;
+ return ERR_PTR(-ENODEV);
- spi = spi_alloc_device(ctlr);
+ spi = spi_alloc_device(lookup.ctlr);
if (!spi) {
- dev_err(&ctlr->dev, "failed to allocate SPI device for %s\n",
+ dev_err(&lookup.ctlr->dev, "failed to allocate SPI device for %s\n",
dev_name(&adev->dev));
- return AE_NO_MEMORY;
+ return ERR_PTR(-ENOMEM);
}
-
ACPI_COMPANION_SET(&spi->dev, adev);
spi->max_speed_hz = lookup.max_speed_hz;
spi->mode |= lookup.mode;
@@ -2458,6 +2521,27 @@ static acpi_status acpi_register_spi_device(struct spi_controller *ctlr,
spi->bits_per_word = lookup.bits_per_word;
spi->chip_select = lookup.chip_select;
+ return spi;
+}
+EXPORT_SYMBOL_GPL(acpi_spi_device_alloc);
+
+static acpi_status acpi_register_spi_device(struct spi_controller *ctlr,
+ struct acpi_device *adev)
+{
+ struct spi_device *spi;
+
+ if (acpi_bus_get_status(adev) || !adev->status.present ||
+ acpi_device_enumerated(adev))
+ return AE_OK;
+
+ spi = acpi_spi_device_alloc(ctlr, adev, -1);
+ if (IS_ERR(spi)) {
+ if (PTR_ERR(spi) == -ENOMEM)
+ return AE_NO_MEMORY;
+ else
+ return AE_OK;
+ }
+
acpi_set_modalias(adev, acpi_device_hid(adev), spi->modalias,
sizeof(spi->modalias));
@@ -2480,10 +2564,10 @@ static acpi_status acpi_register_spi_device(struct spi_controller *ctlr,
static acpi_status acpi_spi_add_device(acpi_handle handle, u32 level,
void *data, void **return_value)
{
+ struct acpi_device *adev = acpi_fetch_acpi_dev(handle);
struct spi_controller *ctlr = data;
- struct acpi_device *adev;
- if (acpi_bus_get_device(handle, &adev))
+ if (!adev)
return AE_OK;
return acpi_register_spi_device(ctlr, adev);
@@ -2729,46 +2813,6 @@ struct spi_controller *__devm_spi_alloc_controller(struct device *dev,
}
EXPORT_SYMBOL_GPL(__devm_spi_alloc_controller);
-#ifdef CONFIG_OF
-static int of_spi_get_gpio_numbers(struct spi_controller *ctlr)
-{
- int nb, i, *cs;
- struct device_node *np = ctlr->dev.of_node;
-
- if (!np)
- return 0;
-
- nb = of_gpio_named_count(np, "cs-gpios");
- ctlr->num_chipselect = max_t(int, nb, ctlr->num_chipselect);
-
- /* Return error only for an incorrectly formed cs-gpios property */
- if (nb == 0 || nb == -ENOENT)
- return 0;
- else if (nb < 0)
- return nb;
-
- cs = devm_kcalloc(&ctlr->dev, ctlr->num_chipselect, sizeof(int),
- GFP_KERNEL);
- ctlr->cs_gpios = cs;
-
- if (!ctlr->cs_gpios)
- return -ENOMEM;
-
- for (i = 0; i < ctlr->num_chipselect; i++)
- cs[i] = -ENOENT;
-
- for (i = 0; i < nb; i++)
- cs[i] = of_get_named_gpio(np, "cs-gpios", i);
-
- return 0;
-}
-#else
-static int of_spi_get_gpio_numbers(struct spi_controller *ctlr)
-{
- return 0;
-}
-#endif
-
/**
* spi_get_gpio_descs() - grab chip select GPIOs for the master
* @ctlr: The SPI master to grab GPIO descriptors for
@@ -2953,22 +2997,15 @@ int spi_register_controller(struct spi_controller *ctlr)
*/
dev_set_name(&ctlr->dev, "spi%u", ctlr->bus_num);
- if (!spi_controller_is_slave(ctlr)) {
- if (ctlr->use_gpio_descriptors) {
- status = spi_get_gpio_descs(ctlr);
- if (status)
- goto free_bus_id;
- /*
- * A controller using GPIO descriptors always
- * supports SPI_CS_HIGH if need be.
- */
- ctlr->mode_bits |= SPI_CS_HIGH;
- } else {
- /* Legacy code path for GPIOs from DT */
- status = of_spi_get_gpio_numbers(ctlr);
- if (status)
- goto free_bus_id;
- }
+ if (!spi_controller_is_slave(ctlr) && ctlr->use_gpio_descriptors) {
+ status = spi_get_gpio_descs(ctlr);
+ if (status)
+ goto free_bus_id;
+ /*
+ * A controller using GPIO descriptors always
+ * supports SPI_CS_HIGH if need be.
+ */
+ ctlr->mode_bits |= SPI_CS_HIGH;
}
/*
@@ -2980,6 +3017,9 @@ int spi_register_controller(struct spi_controller *ctlr)
goto free_bus_id;
}
+ /* setting last_cs to -1 means no chip selected */
+ ctlr->last_cs = -1;
+
status = device_add(&ctlr->dev);
if (status < 0)
goto free_bus_id;
@@ -3457,12 +3497,6 @@ int spi_setup(struct spi_device *spi)
*/
bad_bits = spi->mode & ~(spi->controller->mode_bits | SPI_CS_WORD |
SPI_NO_TX | SPI_NO_RX);
- /*
- * Nothing prevents from working with active-high CS in case if it
- * is driven by GPIO.
- */
- if (gpio_is_valid(spi->cs_gpio))
- bad_bits &= ~SPI_CS_HIGH;
ugly_bits = bad_bits &
(SPI_TX_DUAL | SPI_TX_QUAD | SPI_TX_OCTAL |
SPI_RX_DUAL | SPI_RX_QUAD | SPI_RX_OCTAL);
@@ -3588,8 +3622,7 @@ static int __spi_validate(struct spi_device *spi, struct spi_message *message)
* cs_change is set for each transfer.
*/
if ((spi->mode & SPI_CS_WORD) && (!(ctlr->mode_bits & SPI_CS_WORD) ||
- spi->cs_gpiod ||
- gpio_is_valid(spi->cs_gpio))) {
+ spi->cs_gpiod)) {
size_t maxsize;
int ret;