diff options
Diffstat (limited to 'drivers/spi/spi-pl022.c')
| -rw-r--r-- | drivers/spi/spi-pl022.c | 64 |
1 files changed, 63 insertions, 1 deletions
diff --git a/drivers/spi/spi-pl022.c b/drivers/spi/spi-pl022.c index f1f0a587e4fc..f35f723816ea 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); @@ -2100,6 +2132,10 @@ static int pl022_probe(struct amba_device *adev, const struct amba_id *id) pl022->vendor = id->data; pl022->chipselects = devm_kzalloc(dev, num_cs * sizeof(int), GFP_KERNEL); + if (!pl022->chipselects) { + status = -ENOMEM; + goto err_no_mem; + } /* * Bus Number Which has been Assigned to this SSP controller @@ -2118,6 +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); @@ -2241,6 +2280,7 @@ static int pl022_probe(struct amba_device *adev, const struct amba_id *id) amba_release_regions(adev); err_no_ioregion: err_no_gpio: + err_no_mem: spi_master_put(master); return status; } @@ -2347,6 +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 = { @@ -2356,6 +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 = { @@ -2365,6 +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[] = { @@ -2398,6 +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 }, }; |