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author | Baolin Wang <baolin.wang@spreadtrum.com> | 2017-09-15 15:29:16 +0800 |
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committer | Mark Brown <broonie@kernel.org> | 2017-09-19 12:53:29 +0100 |
commit | 7e2903cb91df1a8b0a202a7cf5c9e3d2f654bc57 (patch) | |
tree | c54b0d07956b237856348504a328e32776f22293 /drivers/spi | |
parent | 2f329595b8db42ceb3de93595a740ac7b24eddba (diff) | |
download | linux-stable-7e2903cb91df1a8b0a202a7cf5c9e3d2f654bc57.tar.gz linux-stable-7e2903cb91df1a8b0a202a7cf5c9e3d2f654bc57.tar.bz2 linux-stable-7e2903cb91df1a8b0a202a7cf5c9e3d2f654bc57.zip |
spi: Add ADI driver for Spreadtrum platform
This patch adds ADI driver based on SPI framework for
Spreadtrum SC9860 platform.
Signed-off-by: Baolin Wang <baolin.wang@spreadtrum.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi')
-rw-r--r-- | drivers/spi/Kconfig | 6 | ||||
-rw-r--r-- | drivers/spi/Makefile | 1 | ||||
-rw-r--r-- | drivers/spi/spi-sprd-adi.c | 419 |
3 files changed, 426 insertions, 0 deletions
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index a75f2a2cf780..0c38a5bfcd74 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -626,6 +626,12 @@ config SPI_SIRF help SPI driver for CSR SiRFprimaII SoCs +config SPI_SPRD_ADI + tristate "Spreadtrum ADI controller" + depends on ARCH_SPRD || COMPILE_TEST + help + ADI driver based on SPI for Spreadtrum SoCs. + config SPI_STM32 tristate "STMicroelectronics STM32 SPI controller" depends on ARCH_STM32 || COMPILE_TEST diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index a3ae2b70cdc3..de5ae2af75f9 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -90,6 +90,7 @@ obj-$(CONFIG_SPI_SH_HSPI) += spi-sh-hspi.o obj-$(CONFIG_SPI_SH_MSIOF) += spi-sh-msiof.o obj-$(CONFIG_SPI_SH_SCI) += spi-sh-sci.o obj-$(CONFIG_SPI_SIRF) += spi-sirf.o +obj-$(CONFIG_SPI_SPRD_ADI) += spi-sprd-adi.o obj-$(CONFIG_SPI_STM32) += spi-stm32.o obj-$(CONFIG_SPI_ST_SSC4) += spi-st-ssc4.o obj-$(CONFIG_SPI_SUN4I) += spi-sun4i.o diff --git a/drivers/spi/spi-sprd-adi.c b/drivers/spi/spi-sprd-adi.c new file mode 100644 index 000000000000..0d481f8a46c2 --- /dev/null +++ b/drivers/spi/spi-sprd-adi.c @@ -0,0 +1,419 @@ +/* + * Copyright (C) 2017 Spreadtrum Communications Inc. + * + * SPDX-License-Identifier: GPL-2.0 + */ + +#include <linux/hwspinlock.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/spi/spi.h> +#include <linux/sizes.h> + +/* Registers definitions for ADI controller */ +#define REG_ADI_CTRL0 0x4 +#define REG_ADI_CHN_PRIL 0x8 +#define REG_ADI_CHN_PRIH 0xc +#define REG_ADI_INT_EN 0x10 +#define REG_ADI_INT_RAW 0x14 +#define REG_ADI_INT_MASK 0x18 +#define REG_ADI_INT_CLR 0x1c +#define REG_ADI_GSSI_CFG0 0x20 +#define REG_ADI_GSSI_CFG1 0x24 +#define REG_ADI_RD_CMD 0x28 +#define REG_ADI_RD_DATA 0x2c +#define REG_ADI_ARM_FIFO_STS 0x30 +#define REG_ADI_STS 0x34 +#define REG_ADI_EVT_FIFO_STS 0x38 +#define REG_ADI_ARM_CMD_STS 0x3c +#define REG_ADI_CHN_EN 0x40 +#define REG_ADI_CHN_ADDR(id) (0x44 + (id - 2) * 4) +#define REG_ADI_CHN_EN1 0x20c + +/* Bits definitions for register REG_ADI_GSSI_CFG0 */ +#define BIT_CLK_ALL_ON BIT(30) + +/* Bits definitions for register REG_ADI_RD_DATA */ +#define BIT_RD_CMD_BUSY BIT(31) +#define RD_ADDR_SHIFT 16 +#define RD_VALUE_MASK GENMASK(15, 0) +#define RD_ADDR_MASK GENMASK(30, 16) + +/* Bits definitions for register REG_ADI_ARM_FIFO_STS */ +#define BIT_FIFO_FULL BIT(11) +#define BIT_FIFO_EMPTY BIT(10) + +/* + * ADI slave devices include RTC, ADC, regulator, charger, thermal and so on. + * The slave devices address offset is always 0x8000 and size is 4K. + */ +#define ADI_SLAVE_ADDR_SIZE SZ_4K +#define ADI_SLAVE_OFFSET 0x8000 + +/* Timeout (ms) for the trylock of hardware spinlocks */ +#define ADI_HWSPINLOCK_TIMEOUT 5000 +/* + * ADI controller has 50 channels including 2 software channels + * and 48 hardware channels. + */ +#define ADI_HW_CHNS 50 + +#define ADI_FIFO_DRAIN_TIMEOUT 1000 +#define ADI_READ_TIMEOUT 2000 +#define REG_ADDR_LOW_MASK GENMASK(11, 0) + +struct sprd_adi { + struct spi_controller *ctlr; + struct device *dev; + void __iomem *base; + struct hwspinlock *hwlock; + unsigned long slave_vbase; + unsigned long slave_pbase; +}; + +static int sprd_adi_check_paddr(struct sprd_adi *sadi, u32 paddr) +{ + if (paddr < sadi->slave_pbase || paddr > + (sadi->slave_pbase + ADI_SLAVE_ADDR_SIZE)) { + dev_err(sadi->dev, + "slave physical address is incorrect, addr = 0x%x\n", + paddr); + return -EINVAL; + } + + return 0; +} + +static unsigned long sprd_adi_to_vaddr(struct sprd_adi *sadi, u32 paddr) +{ + return (paddr - sadi->slave_pbase + sadi->slave_vbase); +} + +static int sprd_adi_drain_fifo(struct sprd_adi *sadi) +{ + u32 timeout = ADI_FIFO_DRAIN_TIMEOUT; + u32 sts; + + do { + sts = readl_relaxed(sadi->base + REG_ADI_ARM_FIFO_STS); + if (sts & BIT_FIFO_EMPTY) + break; + + cpu_relax(); + } while (--timeout); + + if (timeout == 0) { + dev_err(sadi->dev, "drain write fifo timeout\n"); + return -EBUSY; + } + + return 0; +} + +static int sprd_adi_fifo_is_full(struct sprd_adi *sadi) +{ + return readl_relaxed(sadi->base + REG_ADI_ARM_FIFO_STS) & BIT_FIFO_FULL; +} + +static int sprd_adi_read(struct sprd_adi *sadi, u32 reg_paddr, u32 *read_val) +{ + int read_timeout = ADI_READ_TIMEOUT; + u32 val, rd_addr; + + /* + * Set the physical register address need to read into RD_CMD register, + * then ADI controller will start to transfer automatically. + */ + writel_relaxed(reg_paddr, sadi->base + REG_ADI_RD_CMD); + + /* + * Wait read operation complete, the BIT_RD_CMD_BUSY will be set + * simultaneously when writing read command to register, and the + * BIT_RD_CMD_BUSY will be cleared after the read operation is + * completed. + */ + do { + val = readl_relaxed(sadi->base + REG_ADI_RD_DATA); + if (!(val & BIT_RD_CMD_BUSY)) + break; + + cpu_relax(); + } while (--read_timeout); + + if (read_timeout == 0) { + dev_err(sadi->dev, "ADI read timeout\n"); + return -EBUSY; + } + + /* + * The return value includes data and read register address, from bit 0 + * to bit 15 are data, and from bit 16 to bit 30 are read register + * address. Then we can check the returned register address to validate + * data. + */ + rd_addr = (val & RD_ADDR_MASK ) >> RD_ADDR_SHIFT; + + if (rd_addr != (reg_paddr & REG_ADDR_LOW_MASK)) { + dev_err(sadi->dev, "read error, reg addr = 0x%x, val = 0x%x\n", + reg_paddr, val); + return -EIO; + } + + *read_val = val & RD_VALUE_MASK; + return 0; +} + +static int sprd_adi_write(struct sprd_adi *sadi, unsigned long reg, u32 val) +{ + u32 timeout = ADI_FIFO_DRAIN_TIMEOUT; + int ret; + + ret = sprd_adi_drain_fifo(sadi); + if (ret < 0) + return ret; + + /* + * we should wait for write fifo is empty before writing data to PMIC + * registers. + */ + do { + if (!sprd_adi_fifo_is_full(sadi)) { + writel_relaxed(val, (void __iomem *)reg); + break; + } + + cpu_relax(); + } while (--timeout); + + if (timeout == 0) { + dev_err(sadi->dev, "write fifo is full\n"); + return -EBUSY; + } + + return 0; +} + +static int sprd_adi_transfer_one(struct spi_controller *ctlr, + struct spi_device *spi_dev, + struct spi_transfer *t) +{ + struct sprd_adi *sadi = spi_controller_get_devdata(ctlr); + unsigned long flags, virt_reg; + u32 phy_reg, val; + int ret; + + if (t->rx_buf) { + phy_reg = *(u32 *)t->rx_buf + sadi->slave_pbase; + + ret = sprd_adi_check_paddr(sadi, phy_reg); + if (ret) + return ret; + + ret = hwspin_lock_timeout_irqsave(sadi->hwlock, + ADI_HWSPINLOCK_TIMEOUT, + &flags); + if (ret) { + dev_err(sadi->dev, "get the hw lock failed\n"); + return ret; + } + + ret = sprd_adi_read(sadi, phy_reg, &val); + hwspin_unlock_irqrestore(sadi->hwlock, &flags); + if (ret) + return ret; + + *(u32 *)t->rx_buf = val; + } else if (t->tx_buf) { + u32 *p = (u32 *)t->tx_buf; + + /* + * Get the physical register address need to write and convert + * the physical address to virtual address. Since we need + * virtual register address to write. + */ + phy_reg = *p++ + sadi->slave_pbase; + ret = sprd_adi_check_paddr(sadi, phy_reg); + if (ret) + return ret; + + virt_reg = sprd_adi_to_vaddr(sadi, phy_reg); + val = *p; + + ret = hwspin_lock_timeout_irqsave(sadi->hwlock, + ADI_HWSPINLOCK_TIMEOUT, + &flags); + if (ret) { + dev_err(sadi->dev, "get the hw lock failed\n"); + return ret; + } + + ret = sprd_adi_write(sadi, virt_reg, val); + hwspin_unlock_irqrestore(sadi->hwlock, &flags); + if (ret) + return ret; + } else { + dev_err(sadi->dev, "no buffer for transfer\n"); + return -EINVAL; + } + + return 0; +} + +static void sprd_adi_hw_init(struct sprd_adi *sadi) +{ + struct device_node *np = sadi->dev->of_node; + int i, size, chn_cnt; + const __be32 *list; + u32 tmp; + + /* Address bits select default 12 bits */ + writel_relaxed(0, sadi->base + REG_ADI_CTRL0); + + /* Set all channels as default priority */ + writel_relaxed(0, sadi->base + REG_ADI_CHN_PRIL); + writel_relaxed(0, sadi->base + REG_ADI_CHN_PRIH); + + /* Set clock auto gate mode */ + tmp = readl_relaxed(sadi->base + REG_ADI_GSSI_CFG0); + tmp &= ~BIT_CLK_ALL_ON; + writel_relaxed(tmp, sadi->base + REG_ADI_GSSI_CFG0); + + /* Set hardware channels setting */ + list = of_get_property(np, "sprd,hw-channels", &size); + if (!size || !list) { + dev_info(sadi->dev, "no hw channels setting in node\n"); + return; + } + + chn_cnt = size / 8; + for (i = 0; i < chn_cnt; i++) { + u32 value; + u32 chn_id = be32_to_cpu(*list++); + u32 chn_config = be32_to_cpu(*list++); + + /* Channel 0 and 1 are software channels */ + if (chn_id < 2) + continue; + + writel_relaxed(chn_config, sadi->base + + REG_ADI_CHN_ADDR(chn_id)); + + if (chn_id < 31) { + value = readl_relaxed(sadi->base + REG_ADI_CHN_EN); + value |= BIT(chn_id); + writel_relaxed(value, sadi->base + REG_ADI_CHN_EN); + } else if (chn_id < ADI_HW_CHNS) { + value = readl_relaxed(sadi->base + REG_ADI_CHN_EN1); + value |= BIT(chn_id - 32); + writel_relaxed(value, sadi->base + REG_ADI_CHN_EN1); + } + } +} + +static int sprd_adi_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct spi_controller *ctlr; + struct sprd_adi *sadi; + struct resource *res; + u32 num_chipselect; + int ret; + + if (!np) { + dev_err(&pdev->dev, "can not find the adi bus node\n"); + return -ENODEV; + } + + pdev->id = of_alias_get_id(np, "spi"); + num_chipselect = of_get_child_count(np); + + ctlr = spi_alloc_master(&pdev->dev, sizeof(struct sprd_adi)); + if (!ctlr) + return -ENOMEM; + + dev_set_drvdata(&pdev->dev, ctlr); + sadi = spi_controller_get_devdata(ctlr); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + sadi->base = devm_ioremap_resource(&pdev->dev, res); + if (!sadi->base) { + ret = -ENOMEM; + goto put_ctlr; + } + + sadi->slave_vbase = (unsigned long)sadi->base + ADI_SLAVE_OFFSET; + sadi->slave_pbase = res->start + ADI_SLAVE_OFFSET; + sadi->ctlr = ctlr; + sadi->dev = &pdev->dev; + ret = of_hwspin_lock_get_id(np, 0); + if (ret < 0) { + dev_err(&pdev->dev, "can not get the hardware spinlock\n"); + goto put_ctlr; + } + + sadi->hwlock = hwspin_lock_request_specific(ret); + if (!sadi->hwlock) { + ret = -ENXIO; + goto put_ctlr; + } + + sprd_adi_hw_init(sadi); + + ctlr->dev.of_node = pdev->dev.of_node; + ctlr->bus_num = pdev->id; + ctlr->num_chipselect = num_chipselect; + ctlr->flags = SPI_MASTER_HALF_DUPLEX; + ctlr->bits_per_word_mask = 0; + ctlr->transfer_one = sprd_adi_transfer_one; + + ret = devm_spi_register_controller(&pdev->dev, ctlr); + if (ret) { + dev_err(&pdev->dev, "failed to register SPI controller\n"); + goto free_hwlock; + } + + return 0; + +free_hwlock: + hwspin_lock_free(sadi->hwlock); +put_ctlr: + spi_controller_put(ctlr); + return ret; +} + +static int sprd_adi_remove(struct platform_device *pdev) +{ + struct spi_controller *ctlr = dev_get_drvdata(&pdev->dev); + struct sprd_adi *sadi = spi_controller_get_devdata(ctlr); + + hwspin_lock_free(sadi->hwlock); + return 0; +} + +static const struct of_device_id sprd_adi_of_match[] = { + { + .compatible = "sprd,sc9860-adi", + }, + { }, +}; +MODULE_DEVICE_TABLE(of, sprd_adi_of_match); + +static struct platform_driver sprd_adi_driver = { + .driver = { + .name = "sprd-adi", + .owner = THIS_MODULE, + .of_match_table = sprd_adi_of_match, + }, + .probe = sprd_adi_probe, + .remove = sprd_adi_remove, +}; +module_platform_driver(sprd_adi_driver); + +MODULE_DESCRIPTION("Spreadtrum ADI Controller Driver"); +MODULE_AUTHOR("Baolin Wang <Baolin.Wang@spreadtrum.com>"); +MODULE_LICENSE("GPL v2"); |