// SPDX-License-Identifier: GPL-2.0-only /* * Driver for Allwinner A10 PS2 host controller * * Author: Vishnu Patekar * Aaron.maoye */ #include #include #include #include #include #include #include #include #include #define DRIVER_NAME "sun4i-ps2" /* register offset definitions */ #define PS2_REG_GCTL 0x00 /* PS2 Module Global Control Reg */ #define PS2_REG_DATA 0x04 /* PS2 Module Data Reg */ #define PS2_REG_LCTL 0x08 /* PS2 Module Line Control Reg */ #define PS2_REG_LSTS 0x0C /* PS2 Module Line Status Reg */ #define PS2_REG_FCTL 0x10 /* PS2 Module FIFO Control Reg */ #define PS2_REG_FSTS 0x14 /* PS2 Module FIFO Status Reg */ #define PS2_REG_CLKDR 0x18 /* PS2 Module Clock Divider Reg*/ /* PS2 GLOBAL CONTROL REGISTER PS2_GCTL */ #define PS2_GCTL_INTFLAG BIT(4) #define PS2_GCTL_INTEN BIT(3) #define PS2_GCTL_RESET BIT(2) #define PS2_GCTL_MASTER BIT(1) #define PS2_GCTL_BUSEN BIT(0) /* PS2 LINE CONTROL REGISTER */ #define PS2_LCTL_NOACK BIT(18) #define PS2_LCTL_TXDTOEN BIT(8) #define PS2_LCTL_STOPERREN BIT(3) #define PS2_LCTL_ACKERREN BIT(2) #define PS2_LCTL_PARERREN BIT(1) #define PS2_LCTL_RXDTOEN BIT(0) /* PS2 LINE STATUS REGISTER */ #define PS2_LSTS_TXTDO BIT(8) #define PS2_LSTS_STOPERR BIT(3) #define PS2_LSTS_ACKERR BIT(2) #define PS2_LSTS_PARERR BIT(1) #define PS2_LSTS_RXTDO BIT(0) #define PS2_LINE_ERROR_BIT \ (PS2_LSTS_TXTDO | PS2_LSTS_STOPERR | PS2_LSTS_ACKERR | \ PS2_LSTS_PARERR | PS2_LSTS_RXTDO) /* PS2 FIFO CONTROL REGISTER */ #define PS2_FCTL_TXRST BIT(17) #define PS2_FCTL_RXRST BIT(16) #define PS2_FCTL_TXUFIEN BIT(10) #define PS2_FCTL_TXOFIEN BIT(9) #define PS2_FCTL_TXRDYIEN BIT(8) #define PS2_FCTL_RXUFIEN BIT(2) #define PS2_FCTL_RXOFIEN BIT(1) #define PS2_FCTL_RXRDYIEN BIT(0) /* PS2 FIFO STATUS REGISTER */ #define PS2_FSTS_TXUF BIT(10) #define PS2_FSTS_TXOF BIT(9) #define PS2_FSTS_TXRDY BIT(8) #define PS2_FSTS_RXUF BIT(2) #define PS2_FSTS_RXOF BIT(1) #define PS2_FSTS_RXRDY BIT(0) #define PS2_FIFO_ERROR_BIT \ (PS2_FSTS_TXUF | PS2_FSTS_TXOF | PS2_FSTS_RXUF | PS2_FSTS_RXOF) #define PS2_SAMPLE_CLK 1000000 #define PS2_SCLK 125000 struct sun4i_ps2data { struct serio *serio; struct device *dev; /* IO mapping base */ void __iomem *reg_base; /* clock management */ struct clk *clk; /* irq */ spinlock_t lock; int irq; }; static irqreturn_t sun4i_ps2_interrupt(int irq, void *dev_id) { struct sun4i_ps2data *drvdata = dev_id; u32 intr_status; u32 fifo_status; unsigned char byte; unsigned int rxflags = 0; u32 rval; guard(spinlock)(&drvdata->lock); /* Get the PS/2 interrupts and clear them */ intr_status = readl(drvdata->reg_base + PS2_REG_LSTS); fifo_status = readl(drvdata->reg_base + PS2_REG_FSTS); /* Check line status register */ if (intr_status & PS2_LINE_ERROR_BIT) { rxflags = (intr_status & PS2_LINE_ERROR_BIT) ? SERIO_FRAME : 0; rxflags |= (intr_status & PS2_LSTS_PARERR) ? SERIO_PARITY : 0; rxflags |= (intr_status & PS2_LSTS_PARERR) ? SERIO_TIMEOUT : 0; rval = PS2_LSTS_TXTDO | PS2_LSTS_STOPERR | PS2_LSTS_ACKERR | PS2_LSTS_PARERR | PS2_LSTS_RXTDO; writel(rval, drvdata->reg_base + PS2_REG_LSTS); } /* Check FIFO status register */ if (fifo_status & PS2_FIFO_ERROR_BIT) { rval = PS2_FSTS_TXUF | PS2_FSTS_TXOF | PS2_FSTS_TXRDY | PS2_FSTS_RXUF | PS2_FSTS_RXOF | PS2_FSTS_RXRDY; writel(rval, drvdata->reg_base + PS2_REG_FSTS); } rval = (fifo_status >> 16) & 0x3; while (rval--) { byte = readl(drvdata->reg_base + PS2_REG_DATA) & 0xff; serio_interrupt(drvdata->serio, byte, rxflags); } writel(intr_status, drvdata->reg_base + PS2_REG_LSTS); writel(fifo_status, drvdata->reg_base + PS2_REG_FSTS); return IRQ_HANDLED; } static int sun4i_ps2_open(struct serio *serio) { struct sun4i_ps2data *drvdata = serio->port_data; u32 src_clk = 0; u32 clk_scdf; u32 clk_pcdf; u32 rval; /* Set line control and enable interrupt */ rval = PS2_LCTL_STOPERREN | PS2_LCTL_ACKERREN | PS2_LCTL_PARERREN | PS2_LCTL_RXDTOEN; writel(rval, drvdata->reg_base + PS2_REG_LCTL); /* Reset FIFO */ rval = PS2_FCTL_TXRST | PS2_FCTL_RXRST | PS2_FCTL_TXUFIEN | PS2_FCTL_TXOFIEN | PS2_FCTL_RXUFIEN | PS2_FCTL_RXOFIEN | PS2_FCTL_RXRDYIEN; writel(rval, drvdata->reg_base + PS2_REG_FCTL); src_clk = clk_get_rate(drvdata->clk); /* Set clock divider register */ clk_scdf = src_clk / PS2_SAMPLE_CLK - 1; clk_pcdf = PS2_SAMPLE_CLK / PS2_SCLK - 1; rval = (clk_scdf << 8) | clk_pcdf; writel(rval, drvdata->reg_base + PS2_REG_CLKDR); /* Set global control register */ rval = PS2_GCTL_RESET | PS2_GCTL_INTEN | PS2_GCTL_MASTER | PS2_GCTL_BUSEN; guard(spinlock_irqsave)(&drvdata->lock); writel(rval, drvdata->reg_base + PS2_REG_GCTL); return 0; } static void sun4i_ps2_close(struct serio *serio) { struct sun4i_ps2data *drvdata = serio->port_data; u32 rval; /* Shut off the interrupt */ rval = readl(drvdata->reg_base + PS2_REG_GCTL); writel(rval & ~(PS2_GCTL_INTEN), drvdata->reg_base + PS2_REG_GCTL); synchronize_irq(drvdata->irq); } static int sun4i_ps2_write(struct serio *serio, unsigned char val) { unsigned long expire = jiffies + msecs_to_jiffies(10000); struct sun4i_ps2data *drvdata = serio->port_data; do { if (readl(drvdata->reg_base + PS2_REG_FSTS) & PS2_FSTS_TXRDY) { writel(val, drvdata->reg_base + PS2_REG_DATA); return 0; } } while (time_before(jiffies, expire)); return SERIO_TIMEOUT; } static int sun4i_ps2_probe(struct platform_device *pdev) { struct resource *res; /* IO mem resources */ struct sun4i_ps2data *drvdata; struct serio *serio; struct device *dev = &pdev->dev; int error; drvdata = kzalloc(sizeof(*drvdata), GFP_KERNEL); serio = kzalloc(sizeof(*serio), GFP_KERNEL); if (!drvdata || !serio) { error = -ENOMEM; goto err_free_mem; } spin_lock_init(&drvdata->lock); /* IO */ res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!res) { dev_err(dev, "failed to locate registers\n"); error = -ENXIO; goto err_free_mem; } drvdata->reg_base = ioremap(res->start, resource_size(res)); if (!drvdata->reg_base) { dev_err(dev, "failed to map registers\n"); error = -ENOMEM; goto err_free_mem; } drvdata->clk = clk_get(dev, NULL); if (IS_ERR(drvdata->clk)) { error = PTR_ERR(drvdata->clk); dev_err(dev, "couldn't get clock %d\n", error); goto err_ioremap; } error = clk_prepare_enable(drvdata->clk); if (error) { dev_err(dev, "failed to enable clock %d\n", error); goto err_clk; } serio->id.type = SERIO_8042; serio->write = sun4i_ps2_write; serio->open = sun4i_ps2_open; serio->close = sun4i_ps2_close; serio->port_data = drvdata; serio->dev.parent = dev; strscpy(serio->name, dev_name(dev), sizeof(serio->name)); strscpy(serio->phys, dev_name(dev), sizeof(serio->phys)); /* shutoff interrupt */ writel(0, drvdata->reg_base + PS2_REG_GCTL); /* Get IRQ for the device */ drvdata->irq = platform_get_irq(pdev, 0); if (drvdata->irq < 0) { error = drvdata->irq; goto err_disable_clk; } drvdata->serio = serio; drvdata->dev = dev; error = request_irq(drvdata->irq, sun4i_ps2_interrupt, 0, DRIVER_NAME, drvdata); if (error) { dev_err(drvdata->dev, "failed to allocate interrupt %d: %d\n", drvdata->irq, error); goto err_disable_clk; } serio_register_port(serio); platform_set_drvdata(pdev, drvdata); return 0; /* success */ err_disable_clk: clk_disable_unprepare(drvdata->clk); err_clk: clk_put(drvdata->clk); err_ioremap: iounmap(drvdata->reg_base); err_free_mem: kfree(serio); kfree(drvdata); return error; } static void sun4i_ps2_remove(struct platform_device *pdev) { struct sun4i_ps2data *drvdata = platform_get_drvdata(pdev); serio_unregister_port(drvdata->serio); free_irq(drvdata->irq, drvdata); clk_disable_unprepare(drvdata->clk); clk_put(drvdata->clk); iounmap(drvdata->reg_base); kfree(drvdata); } static const struct of_device_id sun4i_ps2_match[] = { { .compatible = "allwinner,sun4i-a10-ps2", }, { }, }; MODULE_DEVICE_TABLE(of, sun4i_ps2_match); static struct platform_driver sun4i_ps2_driver = { .probe = sun4i_ps2_probe, .remove = sun4i_ps2_remove, .driver = { .name = DRIVER_NAME, .of_match_table = sun4i_ps2_match, }, }; module_platform_driver(sun4i_ps2_driver); MODULE_AUTHOR("Vishnu Patekar "); MODULE_AUTHOR("Aaron.maoye "); MODULE_DESCRIPTION("Allwinner A10/Sun4i PS/2 driver"); MODULE_LICENSE("GPL v2");