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-rw-r--r--kernel/drivers/sbus/char/bbc_i2c.c424
1 files changed, 424 insertions, 0 deletions
diff --git a/kernel/drivers/sbus/char/bbc_i2c.c b/kernel/drivers/sbus/char/bbc_i2c.c
new file mode 100644
index 000000000..129967ad3
--- /dev/null
+++ b/kernel/drivers/sbus/char/bbc_i2c.c
@@ -0,0 +1,424 @@
+/* bbc_i2c.c: I2C low-level driver for BBC device on UltraSPARC-III
+ * platforms.
+ *
+ * Copyright (C) 2001, 2008 David S. Miller (davem@davemloft.net)
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <asm/bbc.h>
+#include <asm/io.h>
+
+#include "bbc_i2c.h"
+
+/* Convert this driver to use i2c bus layer someday... */
+#define I2C_PCF_PIN 0x80
+#define I2C_PCF_ESO 0x40
+#define I2C_PCF_ES1 0x20
+#define I2C_PCF_ES2 0x10
+#define I2C_PCF_ENI 0x08
+#define I2C_PCF_STA 0x04
+#define I2C_PCF_STO 0x02
+#define I2C_PCF_ACK 0x01
+
+#define I2C_PCF_START (I2C_PCF_PIN | I2C_PCF_ESO | I2C_PCF_ENI | I2C_PCF_STA | I2C_PCF_ACK)
+#define I2C_PCF_STOP (I2C_PCF_PIN | I2C_PCF_ESO | I2C_PCF_STO | I2C_PCF_ACK)
+#define I2C_PCF_REPSTART ( I2C_PCF_ESO | I2C_PCF_STA | I2C_PCF_ACK)
+#define I2C_PCF_IDLE (I2C_PCF_PIN | I2C_PCF_ESO | I2C_PCF_ACK)
+
+#define I2C_PCF_INI 0x40 /* 1 if not initialized */
+#define I2C_PCF_STS 0x20
+#define I2C_PCF_BER 0x10
+#define I2C_PCF_AD0 0x08
+#define I2C_PCF_LRB 0x08
+#define I2C_PCF_AAS 0x04
+#define I2C_PCF_LAB 0x02
+#define I2C_PCF_BB 0x01
+
+/* The BBC devices have two I2C controllers. The first I2C controller
+ * connects mainly to configuration proms (NVRAM, cpu configuration,
+ * dimm types, etc.). Whereas the second I2C controller connects to
+ * environmental control devices such as fans and temperature sensors.
+ * The second controller also connects to the smartcard reader, if present.
+ */
+
+static void set_device_claimage(struct bbc_i2c_bus *bp, struct platform_device *op, int val)
+{
+ int i;
+
+ for (i = 0; i < NUM_CHILDREN; i++) {
+ if (bp->devs[i].device == op) {
+ bp->devs[i].client_claimed = val;
+ return;
+ }
+ }
+}
+
+#define claim_device(BP,ECHILD) set_device_claimage(BP,ECHILD,1)
+#define release_device(BP,ECHILD) set_device_claimage(BP,ECHILD,0)
+
+struct platform_device *bbc_i2c_getdev(struct bbc_i2c_bus *bp, int index)
+{
+ struct platform_device *op = NULL;
+ int curidx = 0, i;
+
+ for (i = 0; i < NUM_CHILDREN; i++) {
+ if (!(op = bp->devs[i].device))
+ break;
+ if (curidx == index)
+ goto out;
+ op = NULL;
+ curidx++;
+ }
+
+out:
+ if (curidx == index)
+ return op;
+ return NULL;
+}
+
+struct bbc_i2c_client *bbc_i2c_attach(struct bbc_i2c_bus *bp, struct platform_device *op)
+{
+ struct bbc_i2c_client *client;
+ const u32 *reg;
+
+ client = kzalloc(sizeof(*client), GFP_KERNEL);
+ if (!client)
+ return NULL;
+ client->bp = bp;
+ client->op = op;
+
+ reg = of_get_property(op->dev.of_node, "reg", NULL);
+ if (!reg) {
+ kfree(client);
+ return NULL;
+ }
+
+ client->bus = reg[0];
+ client->address = reg[1];
+
+ claim_device(bp, op);
+
+ return client;
+}
+
+void bbc_i2c_detach(struct bbc_i2c_client *client)
+{
+ struct bbc_i2c_bus *bp = client->bp;
+ struct platform_device *op = client->op;
+
+ release_device(bp, op);
+ kfree(client);
+}
+
+static int wait_for_pin(struct bbc_i2c_bus *bp, u8 *status)
+{
+ DECLARE_WAITQUEUE(wait, current);
+ int limit = 32;
+ int ret = 1;
+
+ bp->waiting = 1;
+ add_wait_queue(&bp->wq, &wait);
+ while (limit-- > 0) {
+ long val;
+
+ val = wait_event_interruptible_timeout(
+ bp->wq,
+ (((*status = readb(bp->i2c_control_regs + 0))
+ & I2C_PCF_PIN) == 0),
+ msecs_to_jiffies(250));
+ if (val > 0) {
+ ret = 0;
+ break;
+ }
+ }
+ remove_wait_queue(&bp->wq, &wait);
+ bp->waiting = 0;
+
+ return ret;
+}
+
+int bbc_i2c_writeb(struct bbc_i2c_client *client, unsigned char val, int off)
+{
+ struct bbc_i2c_bus *bp = client->bp;
+ int address = client->address;
+ u8 status;
+ int ret = -1;
+
+ if (bp->i2c_bussel_reg != NULL)
+ writeb(client->bus, bp->i2c_bussel_reg);
+
+ writeb(address, bp->i2c_control_regs + 0x1);
+ writeb(I2C_PCF_START, bp->i2c_control_regs + 0x0);
+ if (wait_for_pin(bp, &status))
+ goto out;
+
+ writeb(off, bp->i2c_control_regs + 0x1);
+ if (wait_for_pin(bp, &status) ||
+ (status & I2C_PCF_LRB) != 0)
+ goto out;
+
+ writeb(val, bp->i2c_control_regs + 0x1);
+ if (wait_for_pin(bp, &status))
+ goto out;
+
+ ret = 0;
+
+out:
+ writeb(I2C_PCF_STOP, bp->i2c_control_regs + 0x0);
+ return ret;
+}
+
+int bbc_i2c_readb(struct bbc_i2c_client *client, unsigned char *byte, int off)
+{
+ struct bbc_i2c_bus *bp = client->bp;
+ unsigned char address = client->address, status;
+ int ret = -1;
+
+ if (bp->i2c_bussel_reg != NULL)
+ writeb(client->bus, bp->i2c_bussel_reg);
+
+ writeb(address, bp->i2c_control_regs + 0x1);
+ writeb(I2C_PCF_START, bp->i2c_control_regs + 0x0);
+ if (wait_for_pin(bp, &status))
+ goto out;
+
+ writeb(off, bp->i2c_control_regs + 0x1);
+ if (wait_for_pin(bp, &status) ||
+ (status & I2C_PCF_LRB) != 0)
+ goto out;
+
+ writeb(I2C_PCF_STOP, bp->i2c_control_regs + 0x0);
+
+ address |= 0x1; /* READ */
+
+ writeb(address, bp->i2c_control_regs + 0x1);
+ writeb(I2C_PCF_START, bp->i2c_control_regs + 0x0);
+ if (wait_for_pin(bp, &status))
+ goto out;
+
+ /* Set PIN back to one so the device sends the first
+ * byte.
+ */
+ (void) readb(bp->i2c_control_regs + 0x1);
+ if (wait_for_pin(bp, &status))
+ goto out;
+
+ writeb(I2C_PCF_ESO | I2C_PCF_ENI, bp->i2c_control_regs + 0x0);
+ *byte = readb(bp->i2c_control_regs + 0x1);
+ if (wait_for_pin(bp, &status))
+ goto out;
+
+ ret = 0;
+
+out:
+ writeb(I2C_PCF_STOP, bp->i2c_control_regs + 0x0);
+ (void) readb(bp->i2c_control_regs + 0x1);
+
+ return ret;
+}
+
+int bbc_i2c_write_buf(struct bbc_i2c_client *client,
+ char *buf, int len, int off)
+{
+ int ret = 0;
+
+ while (len > 0) {
+ ret = bbc_i2c_writeb(client, *buf, off);
+ if (ret < 0)
+ break;
+ len--;
+ buf++;
+ off++;
+ }
+ return ret;
+}
+
+int bbc_i2c_read_buf(struct bbc_i2c_client *client,
+ char *buf, int len, int off)
+{
+ int ret = 0;
+
+ while (len > 0) {
+ ret = bbc_i2c_readb(client, buf, off);
+ if (ret < 0)
+ break;
+ len--;
+ buf++;
+ off++;
+ }
+
+ return ret;
+}
+
+EXPORT_SYMBOL(bbc_i2c_getdev);
+EXPORT_SYMBOL(bbc_i2c_attach);
+EXPORT_SYMBOL(bbc_i2c_detach);
+EXPORT_SYMBOL(bbc_i2c_writeb);
+EXPORT_SYMBOL(bbc_i2c_readb);
+EXPORT_SYMBOL(bbc_i2c_write_buf);
+EXPORT_SYMBOL(bbc_i2c_read_buf);
+
+static irqreturn_t bbc_i2c_interrupt(int irq, void *dev_id)
+{
+ struct bbc_i2c_bus *bp = dev_id;
+
+ /* PIN going from set to clear is the only event which
+ * makes the i2c assert an interrupt.
+ */
+ if (bp->waiting &&
+ !(readb(bp->i2c_control_regs + 0x0) & I2C_PCF_PIN))
+ wake_up_interruptible(&bp->wq);
+
+ return IRQ_HANDLED;
+}
+
+static void reset_one_i2c(struct bbc_i2c_bus *bp)
+{
+ writeb(I2C_PCF_PIN, bp->i2c_control_regs + 0x0);
+ writeb(bp->own, bp->i2c_control_regs + 0x1);
+ writeb(I2C_PCF_PIN | I2C_PCF_ES1, bp->i2c_control_regs + 0x0);
+ writeb(bp->clock, bp->i2c_control_regs + 0x1);
+ writeb(I2C_PCF_IDLE, bp->i2c_control_regs + 0x0);
+}
+
+static struct bbc_i2c_bus * attach_one_i2c(struct platform_device *op, int index)
+{
+ struct bbc_i2c_bus *bp;
+ struct device_node *dp;
+ int entry;
+
+ bp = kzalloc(sizeof(*bp), GFP_KERNEL);
+ if (!bp)
+ return NULL;
+
+ INIT_LIST_HEAD(&bp->temps);
+ INIT_LIST_HEAD(&bp->fans);
+
+ bp->i2c_control_regs = of_ioremap(&op->resource[0], 0, 0x2, "bbc_i2c_regs");
+ if (!bp->i2c_control_regs)
+ goto fail;
+
+ if (op->num_resources == 2) {
+ bp->i2c_bussel_reg = of_ioremap(&op->resource[1], 0, 0x1, "bbc_i2c_bussel");
+ if (!bp->i2c_bussel_reg)
+ goto fail;
+ }
+
+ bp->waiting = 0;
+ init_waitqueue_head(&bp->wq);
+ if (request_irq(op->archdata.irqs[0], bbc_i2c_interrupt,
+ IRQF_SHARED, "bbc_i2c", bp))
+ goto fail;
+
+ bp->index = index;
+ bp->op = op;
+
+ spin_lock_init(&bp->lock);
+
+ entry = 0;
+ for (dp = op->dev.of_node->child;
+ dp && entry < 8;
+ dp = dp->sibling, entry++) {
+ struct platform_device *child_op;
+
+ child_op = of_find_device_by_node(dp);
+ bp->devs[entry].device = child_op;
+ bp->devs[entry].client_claimed = 0;
+ }
+
+ writeb(I2C_PCF_PIN, bp->i2c_control_regs + 0x0);
+ bp->own = readb(bp->i2c_control_regs + 0x01);
+ writeb(I2C_PCF_PIN | I2C_PCF_ES1, bp->i2c_control_regs + 0x0);
+ bp->clock = readb(bp->i2c_control_regs + 0x01);
+
+ printk(KERN_INFO "i2c-%d: Regs at %p, %d devices, own %02x, clock %02x.\n",
+ bp->index, bp->i2c_control_regs, entry, bp->own, bp->clock);
+
+ reset_one_i2c(bp);
+
+ return bp;
+
+fail:
+ if (bp->i2c_bussel_reg)
+ of_iounmap(&op->resource[1], bp->i2c_bussel_reg, 1);
+ if (bp->i2c_control_regs)
+ of_iounmap(&op->resource[0], bp->i2c_control_regs, 2);
+ kfree(bp);
+ return NULL;
+}
+
+extern int bbc_envctrl_init(struct bbc_i2c_bus *bp);
+extern void bbc_envctrl_cleanup(struct bbc_i2c_bus *bp);
+
+static int bbc_i2c_probe(struct platform_device *op)
+{
+ struct bbc_i2c_bus *bp;
+ int err, index = 0;
+
+ bp = attach_one_i2c(op, index);
+ if (!bp)
+ return -EINVAL;
+
+ err = bbc_envctrl_init(bp);
+ if (err) {
+ free_irq(op->archdata.irqs[0], bp);
+ if (bp->i2c_bussel_reg)
+ of_iounmap(&op->resource[0], bp->i2c_bussel_reg, 1);
+ if (bp->i2c_control_regs)
+ of_iounmap(&op->resource[1], bp->i2c_control_regs, 2);
+ kfree(bp);
+ } else {
+ dev_set_drvdata(&op->dev, bp);
+ }
+
+ return err;
+}
+
+static int bbc_i2c_remove(struct platform_device *op)
+{
+ struct bbc_i2c_bus *bp = dev_get_drvdata(&op->dev);
+
+ bbc_envctrl_cleanup(bp);
+
+ free_irq(op->archdata.irqs[0], bp);
+
+ if (bp->i2c_bussel_reg)
+ of_iounmap(&op->resource[0], bp->i2c_bussel_reg, 1);
+ if (bp->i2c_control_regs)
+ of_iounmap(&op->resource[1], bp->i2c_control_regs, 2);
+
+ kfree(bp);
+
+ return 0;
+}
+
+static const struct of_device_id bbc_i2c_match[] = {
+ {
+ .name = "i2c",
+ .compatible = "SUNW,bbc-i2c",
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, bbc_i2c_match);
+
+static struct platform_driver bbc_i2c_driver = {
+ .driver = {
+ .name = "bbc_i2c",
+ .of_match_table = bbc_i2c_match,
+ },
+ .probe = bbc_i2c_probe,
+ .remove = bbc_i2c_remove,
+};
+
+module_platform_driver(bbc_i2c_driver);
+
+MODULE_LICENSE("GPL");