--- /dev/null
+/*
+ * Driver for Allwinner A10 PS2 host controller
+ *
+ * Author: Vishnu Patekar <vishnupatekar0510@gmail.com>
+ * Aaron.maoye <leafy.myeh@newbietech.com>
+ */
+
+#include <linux/module.h>
+#include <linux/serio.h>
+#include <linux/interrupt.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/mod_devicetable.h>
+#include <linux/platform_device.h>
+
+#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;
+
+ spin_lock(&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);
+
+ spin_unlock(&drvdata->lock);
+
+ 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;
+ unsigned long flags;
+
+ /* 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;
+
+ spin_lock_irqsave(&drvdata->lock, flags);
+ writel(rval, drvdata->reg_base + PS2_REG_GCTL);
+ spin_unlock_irqrestore(&drvdata->lock, flags);
+
+ 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;
+ unsigned int irq;
+ int error;
+
+ drvdata = kzalloc(sizeof(struct sun4i_ps2data), GFP_KERNEL);
+ serio = kzalloc(sizeof(struct 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;
+ strlcpy(serio->name, dev_name(dev), sizeof(serio->name));
+ strlcpy(serio->phys, dev_name(dev), sizeof(serio->phys));
+
+ /* shutoff interrupt */
+ writel(0, drvdata->reg_base + PS2_REG_GCTL);
+
+ /* Get IRQ for the device */
+ irq = platform_get_irq(pdev, 0);
+ if (!irq) {
+ dev_err(dev, "no IRQ found\n");
+ error = -ENXIO;
+ goto err_disable_clk;
+ }
+
+ drvdata->irq = irq;
+ 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 int 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);
+
+ return 0;
+}
+
+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 <vishnupatekar0510@gmail.com>");
+MODULE_AUTHOR("Aaron.maoye <leafy.myeh@newbietech.com>");
+MODULE_DESCRIPTION("Allwinner A10/Sun4i PS/2 driver");
+MODULE_LICENSE("GPL v2");
projects / cascardo / linux.git / commitdiff