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-rw-r--r--drivers/spi/spi-pl022.c59
-rw-r--r--include/linux/amba/bus.h5
2 files changed, 63 insertions, 1 deletions
diff --git a/drivers/spi/spi-pl022.c b/drivers/spi/spi-pl022.c
index 7f13f3f7198b..d0741b2eabb4 100644
--- a/drivers/spi/spi-pl022.c
+++ b/drivers/spi/spi-pl022.c
@@ -82,6 +82,7 @@
#define SSP_MIS(r) (r + 0x01C)
#define SSP_ICR(r) (r + 0x020)
#define SSP_DMACR(r) (r + 0x024)
+#define SSP_CSR(r) (r + 0x030) /* vendor extension */
#define SSP_ITCR(r) (r + 0x080)
#define SSP_ITIP(r) (r + 0x084)
#define SSP_ITOP(r) (r + 0x088)
@@ -198,6 +199,12 @@
#define SSP_DMACR_MASK_TXDMAE (0x1UL << 1)
/*
+ * SSP Chip Select Control Register - SSP_CSR
+ * (vendor extension)
+ */
+#define SSP_CSR_CSVALUE_MASK (0x1FUL << 0)
+
+/*
* SSP Integration Test control Register - SSP_ITCR
*/
#define SSP_ITCR_MASK_ITEN (0x1UL << 0)
@@ -313,6 +320,7 @@ enum ssp_writing {
* @extended_cr: 32 bit wide control register 0 with extra
* features and extra features in CR1 as found in the ST variants
* @pl023: supports a subset of the ST extensions called "PL023"
+ * @internal_cs_ctrl: supports chip select control register
*/
struct vendor_data {
int fifodepth;
@@ -321,6 +329,7 @@ struct vendor_data {
bool extended_cr;
bool pl023;
bool loopback;
+ bool internal_cs_ctrl;
};
/**
@@ -440,9 +449,32 @@ static void null_cs_control(u32 command)
pr_debug("pl022: dummy chip select control, CS=0x%x\n", command);
}
+/**
+ * internal_cs_control - Control chip select signals via SSP_CSR.
+ * @pl022: SSP driver private data structure
+ * @command: select/delect the chip
+ *
+ * Used on controller with internal chip select control via SSP_CSR register
+ * (vendor extension). Each of the 5 LSB in the register controls one chip
+ * select signal.
+ */
+static void internal_cs_control(struct pl022 *pl022, u32 command)
+{
+ u32 tmp;
+
+ tmp = readw(SSP_CSR(pl022->virtbase));
+ if (command == SSP_CHIP_SELECT)
+ tmp &= ~BIT(pl022->cur_cs);
+ else
+ tmp |= BIT(pl022->cur_cs);
+ writew(tmp, SSP_CSR(pl022->virtbase));
+}
+
static void pl022_cs_control(struct pl022 *pl022, u32 command)
{
- if (gpio_is_valid(pl022->cur_cs))
+ if (pl022->vendor->internal_cs_ctrl)
+ internal_cs_control(pl022, command);
+ else if (gpio_is_valid(pl022->cur_cs))
gpio_set_value(pl022->cur_cs, command);
else
pl022->cur_chip->cs_control(command);
@@ -2122,6 +2154,9 @@ static int pl022_probe(struct amba_device *adev, const struct amba_id *id)
if (platform_info->num_chipselect && platform_info->chipselects) {
for (i = 0; i < num_cs; i++)
pl022->chipselects[i] = platform_info->chipselects[i];
+ } else if (pl022->vendor->internal_cs_ctrl) {
+ for (i = 0; i < num_cs; i++)
+ pl022->chipselects[i] = i;
} else if (IS_ENABLED(CONFIG_OF)) {
for (i = 0; i < num_cs; i++) {
int cs_gpio = of_get_named_gpio(np, "cs-gpios", i);
@@ -2352,6 +2387,7 @@ static struct vendor_data vendor_arm = {
.extended_cr = false,
.pl023 = false,
.loopback = true,
+ .internal_cs_ctrl = false,
};
static struct vendor_data vendor_st = {
@@ -2361,6 +2397,7 @@ static struct vendor_data vendor_st = {
.extended_cr = true,
.pl023 = false,
.loopback = true,
+ .internal_cs_ctrl = false,
};
static struct vendor_data vendor_st_pl023 = {
@@ -2370,6 +2407,17 @@ static struct vendor_data vendor_st_pl023 = {
.extended_cr = true,
.pl023 = true,
.loopback = false,
+ .internal_cs_ctrl = false,
+};
+
+static struct vendor_data vendor_lsi = {
+ .fifodepth = 8,
+ .max_bpw = 16,
+ .unidir = false,
+ .extended_cr = false,
+ .pl023 = false,
+ .loopback = true,
+ .internal_cs_ctrl = true,
};
static struct amba_id pl022_ids[] = {
@@ -2403,6 +2451,15 @@ static struct amba_id pl022_ids[] = {
.mask = 0xffffffff,
.data = &vendor_st_pl023,
},
+ {
+ /*
+ * PL022 variant that has a chip select control register whih
+ * allows control of 5 output signals nCS[0:4].
+ */
+ .id = 0x000b6022,
+ .mask = 0x000fffff,
+ .data = &vendor_lsi,
+ },
{ 0, 0 },
};
diff --git a/include/linux/amba/bus.h b/include/linux/amba/bus.h
index fdd7e1b61f60..c324f5700d1a 100644
--- a/include/linux/amba/bus.h
+++ b/include/linux/amba/bus.h
@@ -44,10 +44,15 @@ struct amba_driver {
const struct amba_id *id_table;
};
+/*
+ * Constants for the designer field of the Peripheral ID register. When bit 7
+ * is set to '1', bits [6:0] should be the JEP106 manufacturer identity code.
+ */
enum amba_vendor {
AMBA_VENDOR_ARM = 0x41,
AMBA_VENDOR_ST = 0x80,
AMBA_VENDOR_QCOM = 0x51,
+ AMBA_VENDOR_LSI = 0xb6,
};
extern struct bus_type amba_bustype;