spi/pxa2xx: add support for Lynxpoint SPI controllers

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.westerberg@linux.intel.com>
Tested-by: Lu Cao <lucao@marvell.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
This commit is contained in:
Mika Westerberg 2013-01-22 12:26:33 +02:00 committed by Mark Brown
parent a0d2642e92
commit a3496855d9
2 changed files with 109 additions and 3 deletions

View File

@ -310,7 +310,7 @@ config SPI_PXA2XX_DMA
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

View File

@ -32,6 +32,7 @@
#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>
@ -933,6 +934,13 @@ 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) |
@ -1025,6 +1033,99 @@ static void cleanup(struct spi_device *spi)
kfree(chip);
}
#ifdef CONFIG_ACPI
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)
{
struct pxa2xx_spi_master *pdata;
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;
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->clk = devm_clk_get(&pdev->dev, NULL);
ssp->irq = platform_get_irq(pdev, 0);
ssp->type = LPSS_SSP;
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;
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;
}
static struct acpi_device_id pxa2xx_spi_acpi_match[] = {
{ "INT33C0", 0 },
{ "INT33C1", 0 },
{ },
};
MODULE_DEVICE_TABLE(acpi, pxa2xx_spi_acpi_match);
#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;
@ -1036,8 +1137,11 @@ 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);
@ -1064,6 +1168,7 @@ 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;
@ -1272,6 +1377,7 @@ 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,