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path: root/drivers/i2c/busses/i2c-au1550.c
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Diffstat (limited to 'drivers/i2c/busses/i2c-au1550.c')
-rw-r--r--drivers/i2c/busses/i2c-au1550.c177
1 files changed, 110 insertions, 67 deletions
diff --git a/drivers/i2c/busses/i2c-au1550.c b/drivers/i2c/busses/i2c-au1550.c
index 2f684166c43d..1953b26da56a 100644
--- a/drivers/i2c/busses/i2c-au1550.c
+++ b/drivers/i2c/busses/i2c-au1550.c
@@ -30,14 +30,22 @@
#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/module.h>
+#include <linux/platform_device.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/i2c.h>
+#include <linux/slab.h>
#include <asm/mach-au1x00/au1xxx.h>
#include <asm/mach-au1x00/au1xxx_psc.h>
-#include "i2c-au1550.h"
+struct i2c_au1550_data {
+ u32 psc_base;
+ int xfer_timeout;
+ int ack_timeout;
+ struct i2c_adapter adap;
+ struct resource *ioarea;
+};
static int
wait_xfer_done(struct i2c_au1550_data *adap)
@@ -105,7 +113,7 @@ wait_master_done(struct i2c_au1550_data *adap)
}
static int
-do_address(struct i2c_au1550_data *adap, unsigned int addr, int rd)
+do_address(struct i2c_au1550_data *adap, unsigned int addr, int rd, int q)
{
volatile psc_smb_t *sp;
u32 stat;
@@ -134,6 +142,10 @@ do_address(struct i2c_au1550_data *adap, unsigned int addr, int rd)
if (rd)
addr |= 1;
+ /* zero-byte xfers stop immediately */
+ if (q)
+ addr |= PSC_SMBTXRX_STP;
+
/* Put byte into fifo, start up master.
*/
sp->psc_smbtxrx = addr;
@@ -142,7 +154,7 @@ do_address(struct i2c_au1550_data *adap, unsigned int addr, int rd)
au_sync();
if (wait_ack(adap))
return -EIO;
- return 0;
+ return (q) ? wait_master_done(adap) : 0;
}
static u32
@@ -262,7 +274,8 @@ au1550_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, int num)
for (i = 0; !err && i < num; i++) {
p = &msgs[i];
- err = do_address(adap, p->addr, p->flags & I2C_M_RD);
+ err = do_address(adap, p->addr, p->flags & I2C_M_RD,
+ (p->len == 0));
if (err || !p->len)
continue;
if (p->flags & I2C_M_RD)
@@ -294,18 +307,48 @@ static const struct i2c_algorithm au1550_algo = {
* Prior to calling us, the 50MHz clock frequency and routing
* must have been set up for the PSC indicated by the adapter.
*/
-int
-i2c_au1550_add_bus(struct i2c_adapter *i2c_adap)
+static int __devinit
+i2c_au1550_probe(struct platform_device *pdev)
{
- struct i2c_au1550_data *adap = i2c_adap->algo_data;
- volatile psc_smb_t *sp;
- u32 stat;
+ struct i2c_au1550_data *priv;
+ volatile psc_smb_t *sp;
+ struct resource *r;
+ u32 stat;
+ int ret;
+
+ r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!r) {
+ ret = -ENODEV;
+ goto out;
+ }
+
+ priv = kzalloc(sizeof(struct i2c_au1550_data), GFP_KERNEL);
+ if (!priv) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ priv->ioarea = request_mem_region(r->start, r->end - r->start + 1,
+ pdev->name);
+ if (!priv->ioarea) {
+ ret = -EBUSY;
+ goto out_mem;
+ }
- i2c_adap->algo = &au1550_algo;
+ priv->psc_base = r->start;
+ priv->xfer_timeout = 200;
+ priv->ack_timeout = 200;
+
+ priv->adap.id = I2C_HW_AU1550_PSC;
+ priv->adap.nr = pdev->id;
+ priv->adap.algo = &au1550_algo;
+ priv->adap.algo_data = priv;
+ priv->adap.dev.parent = &pdev->dev;
+ strlcpy(priv->adap.name, "Au1xxx PSC I2C", sizeof(priv->adap.name));
/* Now, set up the PSC for SMBus PIO mode.
*/
- sp = (volatile psc_smb_t *)(adap->psc_base);
+ sp = (volatile psc_smb_t *)priv->psc_base;
sp->psc_ctrl = PSC_CTRL_DISABLE;
au_sync();
sp->psc_sel = PSC_SEL_PS_SMBUSMODE;
@@ -343,87 +386,87 @@ i2c_au1550_add_bus(struct i2c_adapter *i2c_adap)
au_sync();
} while ((stat & PSC_SMBSTAT_DR) == 0);
- return i2c_add_adapter(i2c_adap);
-}
+ ret = i2c_add_numbered_adapter(&priv->adap);
+ if (ret == 0) {
+ platform_set_drvdata(pdev, priv);
+ return 0;
+ }
+ /* disable the PSC */
+ sp->psc_smbcfg = 0;
+ sp->psc_ctrl = PSC_CTRL_DISABLE;
+ au_sync();
-int
-i2c_au1550_del_bus(struct i2c_adapter *adap)
+ release_resource(priv->ioarea);
+ kfree(priv->ioarea);
+out_mem:
+ kfree(priv);
+out:
+ return ret;
+}
+
+static int __devexit
+i2c_au1550_remove(struct platform_device *pdev)
{
- return i2c_del_adapter(adap);
+ struct i2c_au1550_data *priv = platform_get_drvdata(pdev);
+ volatile psc_smb_t *sp = (volatile psc_smb_t *)priv->psc_base;
+
+ platform_set_drvdata(pdev, NULL);
+ i2c_del_adapter(&priv->adap);
+ sp->psc_smbcfg = 0;
+ sp->psc_ctrl = PSC_CTRL_DISABLE;
+ au_sync();
+ release_resource(priv->ioarea);
+ kfree(priv->ioarea);
+ kfree(priv);
+ return 0;
}
static int
-pb1550_reg(struct i2c_client *client)
+i2c_au1550_suspend(struct platform_device *pdev, pm_message_t state)
{
+ struct i2c_au1550_data *priv = platform_get_drvdata(pdev);
+ volatile psc_smb_t *sp = (volatile psc_smb_t *)priv->psc_base;
+
+ sp->psc_ctrl = PSC_CTRL_SUSPEND;
+ au_sync();
return 0;
}
static int
-pb1550_unreg(struct i2c_client *client)
+i2c_au1550_resume(struct platform_device *pdev)
{
+ struct i2c_au1550_data *priv = platform_get_drvdata(pdev);
+ volatile psc_smb_t *sp = (volatile psc_smb_t *)priv->psc_base;
+
+ sp->psc_ctrl = PSC_CTRL_ENABLE;
+ au_sync();
+ while (!(sp->psc_smbstat & PSC_SMBSTAT_SR))
+ au_sync();
return 0;
}
-static struct i2c_au1550_data pb1550_i2c_info = {
- SMBUS_PSC_BASE, 200, 200
-};
-
-static struct i2c_adapter pb1550_board_adapter = {
- name: "pb1550 adapter",
- id: I2C_HW_AU1550_PSC,
- algo: NULL,
- algo_data: &pb1550_i2c_info,
- client_register: pb1550_reg,
- client_unregister: pb1550_unreg,
+static struct platform_driver au1xpsc_smbus_driver = {
+ .driver = {
+ .name = "au1xpsc_smbus",
+ .owner = THIS_MODULE,
+ },
+ .probe = i2c_au1550_probe,
+ .remove = __devexit_p(i2c_au1550_remove),
+ .suspend = i2c_au1550_suspend,
+ .resume = i2c_au1550_resume,
};
-/* BIG hack to support the control interface on the Wolfson WM8731
- * audio codec on the Pb1550 board. We get an address and two data
- * bytes to write, create an i2c message, and send it across the
- * i2c transfer function. We do this here because we have access to
- * the i2c adapter structure.
- */
-static struct i2c_msg wm_i2c_msg; /* We don't want this stuff on the stack */
-static u8 i2cbuf[2];
-
-int
-pb1550_wm_codec_write(u8 addr, u8 reg, u8 val)
-{
- wm_i2c_msg.addr = addr;
- wm_i2c_msg.flags = 0;
- wm_i2c_msg.buf = i2cbuf;
- wm_i2c_msg.len = 2;
- i2cbuf[0] = reg;
- i2cbuf[1] = val;
-
- return pb1550_board_adapter.algo->master_xfer(&pb1550_board_adapter, &wm_i2c_msg, 1);
-}
-
static int __init
i2c_au1550_init(void)
{
- printk(KERN_INFO "Au1550 I2C: ");
-
- /* This is where we would set up a 50MHz clock source
- * and routing. On the Pb1550, the SMBus is PSC2, which
- * uses a shared clock with USB. This has been already
- * configured by Yamon as a 48MHz clock, close enough
- * for our work.
- */
- if (i2c_au1550_add_bus(&pb1550_board_adapter) < 0) {
- printk("failed to initialize.\n");
- return -ENODEV;
- }
-
- printk("initialized.\n");
- return 0;
+ return platform_driver_register(&au1xpsc_smbus_driver);
}
static void __exit
i2c_au1550_exit(void)
{
- i2c_au1550_del_bus(&pb1550_board_adapter);
+ platform_driver_unregister(&au1xpsc_smbus_driver);
}
MODULE_AUTHOR("Dan Malek, Embedded Edge, LLC.");