diff options
Diffstat (limited to 'drivers/spi/spi-sprd-adi.c')
-rw-r--r-- | drivers/spi/spi-sprd-adi.c | 536 |
1 files changed, 536 insertions, 0 deletions
diff --git a/drivers/spi/spi-sprd-adi.c b/drivers/spi/spi-sprd-adi.c new file mode 100644 index 000000000..97f44458e --- /dev/null +++ b/drivers/spi/spi-sprd-adi.c @@ -0,0 +1,536 @@ +/* + * Copyright (C) 2017 Spreadtrum Communications Inc. + * + * SPDX-License-Identifier: GPL-2.0 + */ + +#include <linux/delay.h> +#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/reboot.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) + +/* Registers definitions for PMIC watchdog controller */ +#define REG_WDG_LOAD_LOW 0x80 +#define REG_WDG_LOAD_HIGH 0x84 +#define REG_WDG_CTRL 0x88 +#define REG_WDG_LOCK 0xa0 + +/* Bits definitions for register REG_WDG_CTRL */ +#define BIT_WDG_RUN BIT(1) +#define BIT_WDG_RST BIT(3) + +/* Registers definitions for PMIC */ +#define PMIC_RST_STATUS 0xee8 +#define PMIC_MODULE_EN 0xc08 +#define PMIC_CLK_EN 0xc18 +#define BIT_WDG_EN BIT(2) + +/* Definition of PMIC reset status register */ +#define HWRST_STATUS_RECOVERY 0x20 +#define HWRST_STATUS_NORMAL 0x40 +#define HWRST_STATUS_ALARM 0x50 +#define HWRST_STATUS_SLEEP 0x60 +#define HWRST_STATUS_FASTBOOT 0x30 +#define HWRST_STATUS_SPECIAL 0x70 +#define HWRST_STATUS_PANIC 0x80 +#define HWRST_STATUS_CFTREBOOT 0x90 +#define HWRST_STATUS_AUTODLOADER 0xa0 +#define HWRST_STATUS_IQMODE 0xb0 +#define HWRST_STATUS_SPRDISK 0xc0 + +/* Use default timeout 50 ms that converts to watchdog values */ +#define WDG_LOAD_VAL ((50 * 32768) / 1000) +#define WDG_LOAD_MASK GENMASK(15, 0) +#define WDG_UNLOCK_KEY 0xe551 + +struct sprd_adi { + struct spi_controller *ctlr; + struct device *dev; + void __iomem *base; + struct hwspinlock *hwlock; + unsigned long slave_vbase; + unsigned long slave_pbase; + struct notifier_block restart_handler; +}; + +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; + unsigned long flags; + u32 val, rd_addr; + int 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; + } + + /* + * 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"); + ret = -EBUSY; + goto out; + } + + /* + * 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); + ret = -EIO; + goto out; + } + + *read_val = val & RD_VALUE_MASK; + +out: + hwspin_unlock_irqrestore(sadi->hwlock, &flags); + return ret; +} + +static int sprd_adi_write(struct sprd_adi *sadi, u32 reg_paddr, u32 val) +{ + unsigned long reg = sprd_adi_to_vaddr(sadi, reg_paddr); + u32 timeout = ADI_FIFO_DRAIN_TIMEOUT; + unsigned long flags; + int 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_drain_fifo(sadi); + if (ret < 0) + goto out; + + /* + * 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"); + ret = -EBUSY; + } + +out: + hwspin_unlock_irqrestore(sadi->hwlock, &flags); + return ret; +} + +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); + 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 = sprd_adi_read(sadi, phy_reg, &val); + 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; + + val = *p; + ret = sprd_adi_write(sadi, phy_reg, val); + if (ret) + return ret; + } else { + dev_err(sadi->dev, "no buffer for transfer\n"); + return -EINVAL; + } + + return 0; +} + +static int sprd_adi_restart_handler(struct notifier_block *this, + unsigned long mode, void *cmd) +{ + struct sprd_adi *sadi = container_of(this, struct sprd_adi, + restart_handler); + u32 val, reboot_mode = 0; + + if (!cmd) + reboot_mode = HWRST_STATUS_NORMAL; + else if (!strncmp(cmd, "recovery", 8)) + reboot_mode = HWRST_STATUS_RECOVERY; + else if (!strncmp(cmd, "alarm", 5)) + reboot_mode = HWRST_STATUS_ALARM; + else if (!strncmp(cmd, "fastsleep", 9)) + reboot_mode = HWRST_STATUS_SLEEP; + else if (!strncmp(cmd, "bootloader", 10)) + reboot_mode = HWRST_STATUS_FASTBOOT; + else if (!strncmp(cmd, "panic", 5)) + reboot_mode = HWRST_STATUS_PANIC; + else if (!strncmp(cmd, "special", 7)) + reboot_mode = HWRST_STATUS_SPECIAL; + else if (!strncmp(cmd, "cftreboot", 9)) + reboot_mode = HWRST_STATUS_CFTREBOOT; + else if (!strncmp(cmd, "autodloader", 11)) + reboot_mode = HWRST_STATUS_AUTODLOADER; + else if (!strncmp(cmd, "iqmode", 6)) + reboot_mode = HWRST_STATUS_IQMODE; + else if (!strncmp(cmd, "sprdisk", 7)) + reboot_mode = HWRST_STATUS_SPRDISK; + else + reboot_mode = HWRST_STATUS_NORMAL; + + /* Record the reboot mode */ + sprd_adi_read(sadi, sadi->slave_pbase + PMIC_RST_STATUS, &val); + val |= reboot_mode; + sprd_adi_write(sadi, sadi->slave_pbase + PMIC_RST_STATUS, val); + + /* Enable the interface clock of the watchdog */ + sprd_adi_read(sadi, sadi->slave_pbase + PMIC_MODULE_EN, &val); + val |= BIT_WDG_EN; + sprd_adi_write(sadi, sadi->slave_pbase + PMIC_MODULE_EN, val); + + /* Enable the work clock of the watchdog */ + sprd_adi_read(sadi, sadi->slave_pbase + PMIC_CLK_EN, &val); + val |= BIT_WDG_EN; + sprd_adi_write(sadi, sadi->slave_pbase + PMIC_CLK_EN, val); + + /* Unlock the watchdog */ + sprd_adi_write(sadi, sadi->slave_pbase + REG_WDG_LOCK, WDG_UNLOCK_KEY); + + /* Load the watchdog timeout value, 50ms is always enough. */ + sprd_adi_write(sadi, sadi->slave_pbase + REG_WDG_LOAD_HIGH, 0); + sprd_adi_write(sadi, sadi->slave_pbase + REG_WDG_LOAD_LOW, + WDG_LOAD_VAL & WDG_LOAD_MASK); + + /* Start the watchdog to reset system */ + sprd_adi_read(sadi, sadi->slave_pbase + REG_WDG_CTRL, &val); + val |= BIT_WDG_RUN | BIT_WDG_RST; + sprd_adi_write(sadi, sadi->slave_pbase + REG_WDG_CTRL, val); + + /* Lock the watchdog */ + sprd_adi_write(sadi, sadi->slave_pbase + REG_WDG_LOCK, ~WDG_UNLOCK_KEY); + + mdelay(1000); + + dev_emerg(sadi->dev, "Unable to restart system\n"); + return NOTIFY_DONE; +} + +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 (!list || !size) { + 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 < 32) { + 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 (IS_ERR(sadi->base)) { + ret = PTR_ERR(sadi->base); + 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_byname(np, "adi"); + if (ret < 0) { + dev_err(&pdev->dev, "can not get the hardware spinlock\n"); + goto put_ctlr; + } + + sadi->hwlock = devm_hwspin_lock_request_specific(&pdev->dev, 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 put_ctlr; + } + + sadi->restart_handler.notifier_call = sprd_adi_restart_handler; + sadi->restart_handler.priority = 128; + ret = register_restart_handler(&sadi->restart_handler); + if (ret) { + dev_err(&pdev->dev, "can not register restart handler\n"); + goto put_ctlr; + } + + return 0; + +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); + + unregister_restart_handler(&sadi->restart_handler); + 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", + .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"); |