mcp23s08: isolate spi specific parts

Change spi member of struct mcp23s08 to be a ops-specific opaque data
pointer, and move spi specific knowledge out of mcp23s08_probe_one().

No functional change, but is needed to add i2c support.

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

1 files changed, 57 insertions, 24 deletions

diff --git a/drivers/gpio/gpio-mcp23s08.c b/drivers/gpio/gpio-mcp23s08.c
index ef61234c0e03..7b78f940868e 100644
--- a/drivers/gpio/gpio-mcp23s08.c
+++ b/drivers/gpio/gpio-mcp23s08.c
@@ -50,7 +50,6 @@ struct mcp23s08_ops {
 };
 
 struct mcp23s08 {
-        struct spi_device       *spi;
         u8                      addr;
 
         u16                     cache[11];
@@ -60,6 +59,7 @@ struct mcp23s08 {
         struct gpio_chip        chip;
 
         const struct mcp23s08_ops       *ops;
+        void                    *data; /* ops specific data */
 };
 
 /* A given spi_device can represent up to eight mcp23sxx chips
@@ -73,6 +73,8 @@ struct mcp23s08_driver_data {
         struct mcp23s08         chip[];
 };
 
+#ifdef CONFIG_SPI_MASTER
+
 static int mcp23s08_read(struct mcp23s08 *mcp, unsigned reg)
 {
         u8      tx[2], rx[1];
@@ -80,7 +82,7 @@ static int mcp23s08_read(struct mcp23s08 *mcp, unsigned reg)
 
         tx[0] = mcp->addr | 0x01;
         tx[1] = reg;
-        status = spi_write_then_read(mcp->spi, tx, sizeof tx, rx, sizeof rx);
+        status = spi_write_then_read(mcp->data, tx, sizeof tx, rx, sizeof rx);
         return (status < 0) ? status : rx[0];
 }
 
@@ -91,7 +93,7 @@ static int mcp23s08_write(struct mcp23s08 *mcp, unsigned reg, unsigned val)
         tx[0] = mcp->addr;
         tx[1] = reg;
         tx[2] = val;
-        return spi_write_then_read(mcp->spi, tx, sizeof tx, NULL, 0);
+        return spi_write_then_read(mcp->data, tx, sizeof tx, NULL, 0);
 }
 
 static int
@@ -106,7 +108,7 @@ mcp23s08_read_regs(struct mcp23s08 *mcp, unsigned reg, u16 *vals, unsigned n)
         tx[1] = reg;
 
         tmp = (u8 *)vals;
-        status = spi_write_then_read(mcp->spi, tx, sizeof tx, tmp, n);
+        status = spi_write_then_read(mcp->data, tx, sizeof tx, tmp, n);
         if (status >= 0) {
                 while (n--)
                         vals[n] = tmp[n]; /* expand to 16bit */
@@ -121,7 +123,7 @@ static int mcp23s17_read(struct mcp23s08 *mcp, unsigned reg)
 
         tx[0] = mcp->addr | 0x01;
         tx[1] = reg << 1;
-        status = spi_write_then_read(mcp->spi, tx, sizeof tx, rx, sizeof rx);
+        status = spi_write_then_read(mcp->data, tx, sizeof tx, rx, sizeof rx);
         return (status < 0) ? status : (rx[0] | (rx[1] << 8));
 }
 
@@ -133,7 +135,7 @@ static int mcp23s17_write(struct mcp23s08 *mcp, unsigned reg, unsigned val)
         tx[1] = reg << 1;
         tx[2] = val;
         tx[3] = val >> 8;
-        return spi_write_then_read(mcp->spi, tx, sizeof tx, NULL, 0);
+        return spi_write_then_read(mcp->data, tx, sizeof tx, NULL, 0);
 }
 
 static int
@@ -147,7 +149,7 @@ mcp23s17_read_regs(struct mcp23s08 *mcp, unsigned reg, u16 *vals, unsigned n)
         tx[0] = mcp->addr | 0x01;
         tx[1] = reg << 1;
 
-        status = spi_write_then_read(mcp->spi, tx, sizeof tx,
+        status = spi_write_then_read(mcp->data, tx, sizeof tx,
                                      (u8 *)vals, n * 2);
         if (status >= 0) {
                 while (n--)
@@ -169,6 +171,7 @@ static const struct mcp23s08_ops mcp23s17_ops = {
         .read_regs      = mcp23s17_read_regs,
 };
 
+#endif /* CONFIG_SPI_MASTER */
 
 /*----------------------------------------------------------------------*/
 
@@ -296,17 +299,16 @@ done:
 
 /*----------------------------------------------------------------------*/
 
-static int mcp23s08_probe_one(struct spi_device *spi, unsigned addr,
+static int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
+                              void *data, unsigned addr,
                               unsigned type, unsigned base, unsigned pullups)
 {
-        struct mcp23s08_driver_data     *data = spi_get_drvdata(spi);
-        struct mcp23s08                 *mcp = data->mcp[addr];
-        int                             status;
+        int status;
 
         mutex_init(&mcp->lock);
 
-        mcp->spi = spi;
-        mcp->addr = 0x40 | (addr << 1);
+        mcp->data = data;
+        mcp->addr = addr;
 
         mcp->chip.direction_input = mcp23s08_direction_input;
         mcp->chip.get = mcp23s08_get;
@@ -314,18 +316,29 @@ static int mcp23s08_probe_one(struct spi_device *spi, unsigned addr,
         mcp->chip.set = mcp23s08_set;
         mcp->chip.dbg_show = mcp23s08_dbg_show;
 
-        if (type == MCP_TYPE_S17) {
-                mcp->ops = &mcp23s17_ops;
-                mcp->chip.ngpio = 16;
-                mcp->chip.label = "mcp23s17";
-        } else {
+        switch (type) {
+#ifdef CONFIG_SPI_MASTER
+        case MCP_TYPE_S08:
                 mcp->ops = &mcp23s08_ops;
                 mcp->chip.ngpio = 8;
                 mcp->chip.label = "mcp23s08";
+                break;
+
+        case MCP_TYPE_S17:
+                mcp->ops = &mcp23s17_ops;
+                mcp->chip.ngpio = 16;
+                mcp->chip.label = "mcp23s17";
+                break;
+#endif /* CONFIG_SPI_MASTER */
+
+        default:
+                dev_err(dev, "invalid device type (%d)\n", type);
+                return -EINVAL;
         }
+
         mcp->chip.base = base;
         mcp->chip.can_sleep = 1;
-        mcp->chip.dev = &spi->dev;
+        mcp->chip.dev = dev;
         mcp->chip.owner = THIS_MODULE;
 
         /* verify MCP_IOCON.SEQOP = 0, so sequential reads work,
@@ -371,11 +384,13 @@ static int mcp23s08_probe_one(struct spi_device *spi, unsigned addr,
         status = gpiochip_add(&mcp->chip);
 fail:
         if (status < 0)
-                dev_dbg(&spi->dev, "can't setup chip %d, --> %d\n",
-                                addr, status);
+                dev_dbg(dev, "can't setup chip %d, --> %d\n",
+                        addr, status);
         return status;
 }
 
+#ifdef CONFIG_SPI_MASTER
+
 static int mcp23s08_probe(struct spi_device *spi)
 {
         struct mcp23s08_platform_data   *pdata;
@@ -418,7 +433,8 @@ static int mcp23s08_probe(struct spi_device *spi)
                         continue;
                 chips--;
                 data->mcp[addr] = &data->chip[chips];
-                status = mcp23s08_probe_one(spi, addr, type, base,
+                status = mcp23s08_probe_one(data->mcp[addr], &spi->dev, spi,
+                                            0x40 | (addr << 1), type, base,
                                             pdata->chip[addr].pullups);
                 if (status < 0)
                         goto fail;
@@ -488,11 +504,28 @@ static struct spi_driver mcp23s08_driver = {
         },
 };
 
+static int __init mcp23s08_spi_init(void)
+{
+        return spi_register_driver(&mcp23s08_driver);
+}
+
+static void mcp23s08_spi_exit(void)
+{
+        spi_unregister_driver(&mcp23s08_driver);
+}
+
+#else
+
+static int __init mcp23s08_spi_init(void) { return 0; }
+static void mcp23s08_spi_exit(void) { }
+
+#endif /* CONFIG_SPI_MASTER */
+
 /*----------------------------------------------------------------------*/
 
 static int __init mcp23s08_init(void)
 {
-        return spi_register_driver(&mcp23s08_driver);
+        return mcp23s08_spi_init();
 }
 /* register after spi postcore initcall and before
  * subsys initcalls that may rely on these GPIOs
@@ -501,7 +534,7 @@ subsys_initcall(mcp23s08_init);
 
 static void __exit mcp23s08_exit(void)
 {
-        spi_unregister_driver(&mcp23s08_driver);
+        mcp23s08_spi_exit();
 }
 module_exit(mcp23s08_exit);