X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=drivers%2Fgpio%2Fmcp23s08.c;h=8a1b405fefda040f0001a5799299eefbe55f5768;hb=f4446ea046cf719a6d79449bb9175d50a64d963b;hp=7f92fdd5f0e2888b2c719e67873a5a7f0b435267;hpb=cc55875e26e2b85484b196edbada6caf84eb7765;p=linux-2.6-omap-h63xx.git diff --git a/drivers/gpio/mcp23s08.c b/drivers/gpio/mcp23s08.c index 7f92fdd5f0e..8a1b405fefd 100644 --- a/drivers/gpio/mcp23s08.c +++ b/drivers/gpio/mcp23s08.c @@ -40,15 +40,26 @@ struct mcp23s08 { struct spi_device *spi; u8 addr; + u8 cache[11]; /* lock protects the cached values */ struct mutex lock; - u8 cache[11]; struct gpio_chip chip; struct work_struct work; }; +/* A given spi_device can represent up to four mcp23s08 chips + * sharing the same chipselect but using different addresses + * (e.g. chips #0 and #3 might be populated, but not #1 or $2). + * Driver data holds all the per-chip data. + */ +struct mcp23s08_driver_data { + unsigned ngpio; + struct mcp23s08 *mcp[4]; + struct mcp23s08 chip[]; +}; + static int mcp23s08_read(struct mcp23s08 *mcp, unsigned reg) { u8 tx[2], rx[1]; @@ -208,25 +219,18 @@ done: /*----------------------------------------------------------------------*/ -static int mcp23s08_probe(struct spi_device *spi) +static int mcp23s08_probe_one(struct spi_device *spi, unsigned addr, + unsigned base, unsigned pullups) { - struct mcp23s08 *mcp; - struct mcp23s08_platform_data *pdata; + struct mcp23s08_driver_data *data = spi_get_drvdata(spi); + struct mcp23s08 *mcp = data->mcp[addr]; int status; int do_update = 0; - pdata = spi->dev.platform_data; - if (!pdata || pdata->slave > 3 || !pdata->base) - return -ENODEV; - - mcp = kzalloc(sizeof *mcp, GFP_KERNEL); - if (!mcp) - return -ENOMEM; - mutex_init(&mcp->lock); mcp->spi = spi; - mcp->addr = 0x40 | (pdata->slave << 1); + mcp->addr = 0x40 | (addr << 1); mcp->chip.label = "mcp23s08", @@ -236,26 +240,28 @@ static int mcp23s08_probe(struct spi_device *spi) mcp->chip.set = mcp23s08_set; mcp->chip.dbg_show = mcp23s08_dbg_show; - mcp->chip.base = pdata->base; + mcp->chip.base = base; mcp->chip.ngpio = 8; mcp->chip.can_sleep = 1; + mcp->chip.dev = &spi->dev; mcp->chip.owner = THIS_MODULE; - spi_set_drvdata(spi, mcp); - - /* verify MCP_IOCON.SEQOP = 0, so sequential reads work */ + /* verify MCP_IOCON.SEQOP = 0, so sequential reads work, + * and MCP_IOCON.HAEN = 1, so we work with all chips. + */ status = mcp23s08_read(mcp, MCP_IOCON); if (status < 0) goto fail; - if (status & IOCON_SEQOP) { + if ((status & IOCON_SEQOP) || !(status & IOCON_HAEN)) { status &= ~IOCON_SEQOP; + status |= IOCON_HAEN; status = mcp23s08_write(mcp, MCP_IOCON, (u8) status); if (status < 0) goto fail; } /* configure ~100K pullups */ - status = mcp23s08_write(mcp, MCP_GPPU, pdata->pullups); + status = mcp23s08_write(mcp, MCP_GPPU, pullups); if (status < 0) goto fail; @@ -282,11 +288,58 @@ static int mcp23s08_probe(struct spi_device *spi) tx[1] = MCP_IPOL; memcpy(&tx[2], &mcp->cache[MCP_IPOL], sizeof(tx) - 2); status = spi_write_then_read(mcp->spi, tx, sizeof tx, NULL, 0); - - /* FIXME check status... */ + if (status < 0) + goto fail; } status = gpiochip_add(&mcp->chip); +fail: + if (status < 0) + dev_dbg(&spi->dev, "can't setup chip %d, --> %d\n", + addr, status); + return status; +} + +static int mcp23s08_probe(struct spi_device *spi) +{ + struct mcp23s08_platform_data *pdata; + unsigned addr; + unsigned chips = 0; + struct mcp23s08_driver_data *data; + int status; + unsigned base; + + pdata = spi->dev.platform_data; + if (!pdata || !gpio_is_valid(pdata->base)) + return -ENODEV; + + for (addr = 0; addr < 4; addr++) { + if (!pdata->chip[addr].is_present) + continue; + chips++; + } + if (!chips) + return -ENODEV; + + data = kzalloc(sizeof *data + chips * sizeof(struct mcp23s08), + GFP_KERNEL); + if (!data) + return -ENOMEM; + spi_set_drvdata(spi, data); + + base = pdata->base; + for (addr = 0; addr < 4; addr++) { + if (!pdata->chip[addr].is_present) + continue; + chips--; + data->mcp[addr] = &data->chip[chips]; + status = mcp23s08_probe_one(spi, addr, base, + pdata->chip[addr].pullups); + if (status < 0) + goto fail; + base += 8; + } + data->ngpio = base - pdata->base; /* NOTE: these chips have a relatively sane IRQ framework, with * per-signal masking and level/edge triggering. It's not yet @@ -294,8 +347,9 @@ static int mcp23s08_probe(struct spi_device *spi) */ if (pdata->setup) { - status = pdata->setup(spi, mcp->chip.base, - mcp->chip.ngpio, pdata->context); + status = pdata->setup(spi, + pdata->base, data->ngpio, + pdata->context); if (status < 0) dev_dbg(&spi->dev, "setup --> %d\n", status); } @@ -303,19 +357,29 @@ static int mcp23s08_probe(struct spi_device *spi) return 0; fail: - kfree(mcp); + for (addr = 0; addr < 4; addr++) { + int tmp; + + if (!data->mcp[addr]) + continue; + tmp = gpiochip_remove(&data->mcp[addr]->chip); + if (tmp < 0) + dev_err(&spi->dev, "%s --> %d\n", "remove", tmp); + } + kfree(data); return status; } static int mcp23s08_remove(struct spi_device *spi) { - struct mcp23s08 *mcp = spi_get_drvdata(spi); + struct mcp23s08_driver_data *data = spi_get_drvdata(spi); struct mcp23s08_platform_data *pdata = spi->dev.platform_data; + unsigned addr; int status = 0; if (pdata->teardown) { status = pdata->teardown(spi, - mcp->chip.base, mcp->chip.ngpio, + pdata->base, data->ngpio, pdata->context); if (status < 0) { dev_err(&spi->dev, "%s --> %d\n", "teardown", status); @@ -323,11 +387,20 @@ static int mcp23s08_remove(struct spi_device *spi) } } - status = gpiochip_remove(&mcp->chip); + for (addr = 0; addr < 4; addr++) { + int tmp; + + if (!data->mcp[addr]) + continue; + + tmp = gpiochip_remove(&data->mcp[addr]->chip); + if (tmp < 0) { + dev_err(&spi->dev, "%s --> %d\n", "remove", tmp); + status = tmp; + } + } if (status == 0) - kfree(mcp); - else - dev_err(&spi->dev, "%s --> %d\n", "remove", status); + kfree(data); return status; } @@ -355,4 +428,3 @@ static void __exit mcp23s08_exit(void) module_exit(mcp23s08_exit); MODULE_LICENSE("GPL"); -