Intel Lynxpoint PCH Low Power Subsystem has two general purpose SPI
controllers that are LPSS_SSP compatible. These controllers are enumerated
from ACPI namespace with ACPI IDs INT33C0 and INT33C1.
Signed-off-by: Mika Westerberg <mika.westerb...@linux.intel.com>
---
drivers/spi/Kconfig | 2 +-
drivers/spi/spi-pxa2xx.c | 131 +++++++++++++++++++++++++++++++++++++++++++++-
2 files changed, 130 insertions(+), 3 deletions(-)
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index a90393d..bf1d3b5 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -299,7 +299,7 @@ config SPI_PPC4xx
config SPI_PXA2XX
tristate "PXA2xx SSP SPI master"
- depends on ARCH_PXA || PCI
+ depends on ARCH_PXA || PCI || ACPI
select PXA_SSP if ARCH_PXA
help
This enables using a PXA2xx or Sodaville SSP port as a SPI master
diff --git a/drivers/spi/spi-pxa2xx.c b/drivers/spi/spi-pxa2xx.c
index d6295c0..9ebbfcf 100644
--- a/drivers/spi/spi-pxa2xx.c
+++ b/drivers/spi/spi-pxa2xx.c
@@ -37,6 +37,7 @@
#include <linux/slab.h>
#include <linux/clk.h>
#include <linux/pm_runtime.h>
+#include <linux/acpi.h>
#include <asm/io.h>
#include <asm/irq.h>
@@ -1916,6 +1917,13 @@ static int setup(struct spi_device *spi)
chip->dma_threshold = 0;
if (chip_info->enable_loopback)
chip->cr1 = SSCR1_LBM;
+ } else if (ACPI_HANDLE(&spi->dev)) {
+ /*
+ * Slave devices enumerated from ACPI namespace don't
+ * usually have chip_info but we still might want to use
+ * DMA with them.
+ */
+ chip->enable_dma = drv_data->master_info->enable_dma;
}
chip->threshold = (SSCR1_RxTresh(rx_thres) & SSCR1_RFT) |
@@ -2007,6 +2015,120 @@ static void cleanup(struct spi_device *spi)
kfree(chip);
}
+#ifdef CONFIG_ACPI
+struct pxa2xx_spi_acpi_config {
+ enum pxa_ssp_type type;
+ unsigned long clk_rate;
+};
+
+/* Lynxpoint SPI controllers */
+static const struct pxa2xx_spi_acpi_config lpt_acpi_config = {
+ .type = LPSS_SSP,
+ .clk_rate = 100000000,
+};
+
+static struct acpi_device_id pxa2xx_spi_acpi_match[] = {
+ { "INT33C0", (kernel_ulong_t)&lpt_acpi_config },
+ { "INT33C1", (kernel_ulong_t)&lpt_acpi_config },
+ { },
+};
+MODULE_DEVICE_TABLE(acpi, pxa2xx_spi_acpi_match);
+
+static int pxa2xx_spi_acpi_add_dma(struct acpi_resource *res, void *data)
+{
+ struct pxa2xx_spi_master *pdata = data;
+
+ if (res->type == ACPI_RESOURCE_TYPE_FIXED_DMA) {
+ const struct acpi_resource_fixed_dma *dma;
+
+ dma = &res->data.fixed_dma;
+ if (pdata->tx_slave_id < 0) {
+ pdata->tx_slave_id = dma->request_lines;
+ pdata->tx_chan_id = dma->channels;
+ } else if (pdata->rx_slave_id < 0) {
+ pdata->rx_slave_id = dma->request_lines;
+ pdata->rx_chan_id = dma->channels;
+ }
+ }
+
+ /* Tell the ACPI core to skip this resource */
+ return 1;
+}
+
+static struct pxa2xx_spi_master *
+pxa2xx_spi_acpi_get_pdata(struct platform_device *pdev)
+{
+ const struct pxa2xx_spi_acpi_config *conf;
+ struct pxa2xx_spi_master *pdata;
+ const struct acpi_device_id *id;
+ struct list_head resource_list;
+ struct acpi_device *adev;
+ struct ssp_device *ssp;
+ struct resource *res;
+ int devid;
+
+ if (!ACPI_HANDLE(&pdev->dev) ||
+ acpi_bus_get_device(ACPI_HANDLE(&pdev->dev), &adev))
+ return NULL;
+
+ id = acpi_match_device(pxa2xx_spi_acpi_match, &pdev->dev);
+ if (!id)
+ return NULL;
+
+ conf = (const struct pxa2xx_spi_acpi_config *)id->driver_data;
+ if (!conf)
+ return NULL;
+
+ pdata = devm_kzalloc(&pdev->dev, sizeof(*ssp), GFP_KERNEL);
+ if (!pdata) {
+ dev_err(&pdev->dev,
+ "failed to allocate memory for platform data\n");
+ return NULL;
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return NULL;
+
+ ssp = &pdata->ssp;
+
+ ssp->phys_base = res->start;
+ ssp->mmio_base = devm_request_and_ioremap(&pdev->dev, res);
+ if (!ssp->mmio_base) {
+ dev_err(&pdev->dev, "failed to ioremap mmio_base\n");
+ return NULL;
+ }
+
+ ssp->irq = platform_get_irq(pdev, 0);
+ ssp->type = conf->type;
+ ssp->pdev = pdev;
+
+ ssp->port_id = -1;
+ if (adev->pnp.unique_id && !kstrtoint(adev->pnp.unique_id, 0, &devid))
+ ssp->port_id = devid;
+
+ pdata->num_chipselect = 1;
+ pdata->rx_slave_id = -1;
+ pdata->tx_slave_id = -1;
+ pdata->fixed_clk_rate = conf->clk_rate;
+
+ INIT_LIST_HEAD(&resource_list);
+ acpi_dev_get_resources(adev, &resource_list, pxa2xx_spi_acpi_add_dma,
+ pdata);
+ acpi_dev_free_resource_list(&resource_list);
+
+ pdata->enable_dma = pdata->rx_slave_id >= 0 && pdata->tx_slave_id >= 0;
+
+ return pdata;
+}
+#else
+static inline struct pxa2xx_spi_master *
+pxa2xx_spi_acpi_get_pdata(struct platform_device *pdev)
+{
+ return NULL;
+}
+#endif
+
static int pxa2xx_spi_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
@@ -2018,8 +2140,11 @@ static int pxa2xx_spi_probe(struct platform_device *pdev)
platform_info = dev_get_platdata(dev);
if (!platform_info) {
- dev_err(&pdev->dev, "missing platform data\n");
- return -ENODEV;
+ platform_info = pxa2xx_spi_acpi_get_pdata(pdev);
+ if (!platform_info) {
+ dev_err(&pdev->dev, "missing platform data\n");
+ return -ENODEV;
+ }
}
ssp = pxa_ssp_request(pdev->id, pdev->name);
@@ -2046,6 +2171,7 @@ static int pxa2xx_spi_probe(struct platform_device *pdev)
master->dev.parent = &pdev->dev;
master->dev.of_node = pdev->dev.of_node;
+ ACPI_HANDLE_SET(&master->dev, ACPI_HANDLE(&pdev->dev));
/* the spi->mode bits understood by this driver: */
master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
@@ -2252,6 +2378,7 @@ static struct platform_driver driver = {
.name = "pxa2xx-spi",
.owner = THIS_MODULE,
.pm = &pxa2xx_spi_pm_ops,
+ .acpi_match_table = ACPI_PTR(pxa2xx_spi_acpi_match),
},
.probe = pxa2xx_spi_probe,
.remove = pxa2xx_spi_remove,
--
1.7.10.4
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