From: Linus Torvalds Date: Sat, 14 Aug 2010 18:54:09 +0000 (-0700) Subject: Merge branch 'next-spi' of git://git.secretlab.ca/git/linux-2.6 X-Git-Tag: v2.6.36-rc1~19 X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=commitdiff_plain;h=b171aa27700c78511086a759383b033949c9d7f0;hp=11ac552477e32835cb6970bf0a70c210807f5673 Merge branch 'next-spi' of git://git.secretlab.ca/git/linux-2.6 * 'next-spi' of git://git.secretlab.ca/git/linux-2.6: spi/amba_pl022: Fix probe and remove hook section annotations. spi/mpc5121: change annotations for probe and remove functions spi/bitbang: reinitialize transfer parameters for every message spi/spi-gpio: add support for controllers without MISO or MOSI pin spi/bitbang: add support for SPI_MASTER_NO_{TX, RX} modes SPI100k: Fix 8-bit and RX-only transfers spi/mmc_spi: mmc_spi adaptations for SPI bus locking API spi/mmc_spi: SPI bus locking API, using mutex Fix trivial conflict in drivers/spi/mpc512x_psc_spi.c due to 'struct of_device' => 'struct platform_device' rename and __init/__exit to __devinit/__devexit fix. --- diff --git a/drivers/mmc/host/mmc_spi.c b/drivers/mmc/host/mmc_spi.c index 1145ea0792e6..62a35822003e 100644 --- a/drivers/mmc/host/mmc_spi.c +++ b/drivers/mmc/host/mmc_spi.c @@ -182,7 +182,7 @@ mmc_spi_readbytes(struct mmc_spi_host *host, unsigned len) host->data_dma, sizeof(*host->data), DMA_FROM_DEVICE); - status = spi_sync(host->spi, &host->readback); + status = spi_sync_locked(host->spi, &host->readback); if (host->dma_dev) dma_sync_single_for_cpu(host->dma_dev, @@ -541,7 +541,7 @@ mmc_spi_command_send(struct mmc_spi_host *host, host->data_dma, sizeof(*host->data), DMA_BIDIRECTIONAL); } - status = spi_sync(host->spi, &host->m); + status = spi_sync_locked(host->spi, &host->m); if (host->dma_dev) dma_sync_single_for_cpu(host->dma_dev, @@ -685,7 +685,7 @@ mmc_spi_writeblock(struct mmc_spi_host *host, struct spi_transfer *t, host->data_dma, sizeof(*scratch), DMA_BIDIRECTIONAL); - status = spi_sync(spi, &host->m); + status = spi_sync_locked(spi, &host->m); if (status != 0) { dev_dbg(&spi->dev, "write error (%d)\n", status); @@ -822,7 +822,7 @@ mmc_spi_readblock(struct mmc_spi_host *host, struct spi_transfer *t, DMA_FROM_DEVICE); } - status = spi_sync(spi, &host->m); + status = spi_sync_locked(spi, &host->m); if (host->dma_dev) { dma_sync_single_for_cpu(host->dma_dev, @@ -1018,7 +1018,7 @@ mmc_spi_data_do(struct mmc_spi_host *host, struct mmc_command *cmd, host->data_dma, sizeof(*scratch), DMA_BIDIRECTIONAL); - tmp = spi_sync(spi, &host->m); + tmp = spi_sync_locked(spi, &host->m); if (host->dma_dev) dma_sync_single_for_cpu(host->dma_dev, @@ -1084,6 +1084,9 @@ static void mmc_spi_request(struct mmc_host *mmc, struct mmc_request *mrq) } #endif + /* request exclusive bus access */ + spi_bus_lock(host->spi->master); + /* issue command; then optionally data and stop */ status = mmc_spi_command_send(host, mrq, mrq->cmd, mrq->data != NULL); if (status == 0 && mrq->data) { @@ -1094,6 +1097,9 @@ static void mmc_spi_request(struct mmc_host *mmc, struct mmc_request *mrq) mmc_cs_off(host); } + /* release the bus */ + spi_bus_unlock(host->spi->master); + mmc_request_done(host->mmc, mrq); } @@ -1290,23 +1296,6 @@ mmc_spi_detect_irq(int irq, void *mmc) return IRQ_HANDLED; } -struct count_children { - unsigned n; - struct bus_type *bus; -}; - -static int maybe_count_child(struct device *dev, void *c) -{ - struct count_children *ccp = c; - - if (dev->bus == ccp->bus) { - if (ccp->n) - return -EBUSY; - ccp->n++; - } - return 0; -} - static int mmc_spi_probe(struct spi_device *spi) { void *ones; @@ -1338,32 +1327,6 @@ static int mmc_spi_probe(struct spi_device *spi) return status; } - /* We can use the bus safely iff nobody else will interfere with us. - * Most commands consist of one SPI message to issue a command, then - * several more to collect its response, then possibly more for data - * transfer. Clocking access to other devices during that period will - * corrupt the command execution. - * - * Until we have software primitives which guarantee non-interference, - * we'll aim for a hardware-level guarantee. - * - * REVISIT we can't guarantee another device won't be added later... - */ - if (spi->master->num_chipselect > 1) { - struct count_children cc; - - cc.n = 0; - cc.bus = spi->dev.bus; - status = device_for_each_child(spi->dev.parent, &cc, - maybe_count_child); - if (status < 0) { - dev_err(&spi->dev, "can't share SPI bus\n"); - return status; - } - - dev_warn(&spi->dev, "ASSUMING SPI bus stays unshared!\n"); - } - /* We need a supply of ones to transmit. This is the only time * the CPU touches these, so cache coherency isn't a concern. * diff --git a/drivers/spi/amba-pl022.c b/drivers/spi/amba-pl022.c index f0a1418ce660..acd35d1ebd12 100644 --- a/drivers/spi/amba-pl022.c +++ b/drivers/spi/amba-pl022.c @@ -1723,7 +1723,7 @@ static void pl022_cleanup(struct spi_device *spi) } -static int __init +static int __devinit pl022_probe(struct amba_device *adev, struct amba_id *id) { struct device *dev = &adev->dev; @@ -1838,7 +1838,7 @@ pl022_probe(struct amba_device *adev, struct amba_id *id) return status; } -static int __exit +static int __devexit pl022_remove(struct amba_device *adev) { struct pl022 *pl022 = amba_get_drvdata(adev); @@ -1970,7 +1970,7 @@ static struct amba_driver pl022_driver = { }, .id_table = pl022_ids, .probe = pl022_probe, - .remove = __exit_p(pl022_remove), + .remove = __devexit_p(pl022_remove), .suspend = pl022_suspend, .resume = pl022_resume, }; diff --git a/drivers/spi/mpc512x_psc_spi.c b/drivers/spi/mpc512x_psc_spi.c index cddbfceb324f..77d9e7ee8b27 100644 --- a/drivers/spi/mpc512x_psc_spi.c +++ b/drivers/spi/mpc512x_psc_spi.c @@ -406,9 +406,9 @@ static irqreturn_t mpc512x_psc_spi_isr(int irq, void *dev_id) } /* bus_num is used only for the case dev->platform_data == NULL */ -static int __init mpc512x_psc_spi_do_probe(struct device *dev, u32 regaddr, - u32 size, unsigned int irq, - s16 bus_num) +static int __devinit mpc512x_psc_spi_do_probe(struct device *dev, u32 regaddr, + u32 size, unsigned int irq, + s16 bus_num) { struct fsl_spi_platform_data *pdata = dev->platform_data; struct mpc512x_psc_spi *mps; @@ -492,7 +492,7 @@ free_master: return ret; } -static int __exit mpc512x_psc_spi_do_remove(struct device *dev) +static int __devexit mpc512x_psc_spi_do_remove(struct device *dev) { struct spi_master *master = dev_get_drvdata(dev); struct mpc512x_psc_spi *mps = spi_master_get_devdata(master); @@ -507,8 +507,8 @@ static int __exit mpc512x_psc_spi_do_remove(struct device *dev) return 0; } -static int __init mpc512x_psc_spi_of_probe(struct platform_device *op, - const struct of_device_id *match) +static int __devinit mpc512x_psc_spi_of_probe(struct platform_device *op, + const struct of_device_id *match) { const u32 *regaddr_p; u64 regaddr64, size64; @@ -539,7 +539,7 @@ static int __init mpc512x_psc_spi_of_probe(struct platform_device *op, irq_of_parse_and_map(op->dev.of_node, 0), id); } -static int __exit mpc512x_psc_spi_of_remove(struct platform_device *op) +static int __devexit mpc512x_psc_spi_of_remove(struct platform_device *op) { return mpc512x_psc_spi_do_remove(&op->dev); } @@ -553,7 +553,7 @@ MODULE_DEVICE_TABLE(of, mpc512x_psc_spi_of_match); static struct of_platform_driver mpc512x_psc_spi_of_driver = { .probe = mpc512x_psc_spi_of_probe, - .remove = __exit_p(mpc512x_psc_spi_of_remove), + .remove = __devexit_p(mpc512x_psc_spi_of_remove), .driver = { .name = "mpc512x-psc-spi", .owner = THIS_MODULE, diff --git a/drivers/spi/omap_spi_100k.c b/drivers/spi/omap_spi_100k.c index 24668b30a52d..9bd1c92ad96e 100644 --- a/drivers/spi/omap_spi_100k.c +++ b/drivers/spi/omap_spi_100k.c @@ -141,7 +141,12 @@ static void spi100k_write_data(struct spi_master *master, int len, int data) { struct omap1_spi100k *spi100k = spi_master_get_devdata(master); - /* write 16-bit word */ + /* write 16-bit word, shifting 8-bit data if necessary */ + if (len <= 8) { + data <<= 8; + len = 16; + } + spi100k_enable_clock(master); writew( data , spi100k->base + SPI_TX_MSB); @@ -162,6 +167,10 @@ static int spi100k_read_data(struct spi_master *master, int len) int dataH,dataL; struct omap1_spi100k *spi100k = spi_master_get_devdata(master); + /* Always do at least 16 bits */ + if (len <= 8) + len = 16; + spi100k_enable_clock(master); writew(SPI_CTRL_SEN(0) | SPI_CTRL_WORD_SIZE(len) | @@ -214,10 +223,6 @@ omap1_spi100k_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) c = count; word_len = cs->word_len; - /* RX_ONLY mode needs dummy data in TX reg */ - if (xfer->tx_buf == NULL) - spi100k_write_data(spi->master,word_len, 0); - if (word_len <= 8) { u8 *rx; const u8 *tx; @@ -227,9 +232,9 @@ omap1_spi100k_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) do { c-=1; if (xfer->tx_buf != NULL) - spi100k_write_data(spi->master,word_len, *tx); + spi100k_write_data(spi->master, word_len, *tx++); if (xfer->rx_buf != NULL) - *rx = spi100k_read_data(spi->master,word_len); + *rx++ = spi100k_read_data(spi->master, word_len); } while(c); } else if (word_len <= 16) { u16 *rx; @@ -380,10 +385,6 @@ static void omap1_spi100k_work(struct work_struct *work) if (t->len) { unsigned count; - /* RX_ONLY mode needs dummy data in TX reg */ - if (t->tx_buf == NULL) - spi100k_write_data(spi->master, 8, 0); - count = omap1_spi100k_txrx_pio(spi, t); m->actual_length += count; diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 1bb1b88780ce..a9e5c79ae52a 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -528,6 +528,10 @@ int spi_register_master(struct spi_master *master) dynamic = 1; } + spin_lock_init(&master->bus_lock_spinlock); + mutex_init(&master->bus_lock_mutex); + master->bus_lock_flag = 0; + /* register the device, then userspace will see it. * registration fails if the bus ID is in use. */ @@ -670,6 +674,35 @@ int spi_setup(struct spi_device *spi) } EXPORT_SYMBOL_GPL(spi_setup); +static int __spi_async(struct spi_device *spi, struct spi_message *message) +{ + struct spi_master *master = spi->master; + + /* Half-duplex links include original MicroWire, and ones with + * only one data pin like SPI_3WIRE (switches direction) or where + * either MOSI or MISO is missing. They can also be caused by + * software limitations. + */ + if ((master->flags & SPI_MASTER_HALF_DUPLEX) + || (spi->mode & SPI_3WIRE)) { + struct spi_transfer *xfer; + unsigned flags = master->flags; + + list_for_each_entry(xfer, &message->transfers, transfer_list) { + if (xfer->rx_buf && xfer->tx_buf) + return -EINVAL; + if ((flags & SPI_MASTER_NO_TX) && xfer->tx_buf) + return -EINVAL; + if ((flags & SPI_MASTER_NO_RX) && xfer->rx_buf) + return -EINVAL; + } + } + + message->spi = spi; + message->status = -EINPROGRESS; + return master->transfer(spi, message); +} + /** * spi_async - asynchronous SPI transfer * @spi: device with which data will be exchanged @@ -702,33 +735,68 @@ EXPORT_SYMBOL_GPL(spi_setup); int spi_async(struct spi_device *spi, struct spi_message *message) { struct spi_master *master = spi->master; + int ret; + unsigned long flags; - /* Half-duplex links include original MicroWire, and ones with - * only one data pin like SPI_3WIRE (switches direction) or where - * either MOSI or MISO is missing. They can also be caused by - * software limitations. - */ - if ((master->flags & SPI_MASTER_HALF_DUPLEX) - || (spi->mode & SPI_3WIRE)) { - struct spi_transfer *xfer; - unsigned flags = master->flags; + spin_lock_irqsave(&master->bus_lock_spinlock, flags); - list_for_each_entry(xfer, &message->transfers, transfer_list) { - if (xfer->rx_buf && xfer->tx_buf) - return -EINVAL; - if ((flags & SPI_MASTER_NO_TX) && xfer->tx_buf) - return -EINVAL; - if ((flags & SPI_MASTER_NO_RX) && xfer->rx_buf) - return -EINVAL; - } - } + if (master->bus_lock_flag) + ret = -EBUSY; + else + ret = __spi_async(spi, message); - message->spi = spi; - message->status = -EINPROGRESS; - return master->transfer(spi, message); + spin_unlock_irqrestore(&master->bus_lock_spinlock, flags); + + return ret; } EXPORT_SYMBOL_GPL(spi_async); +/** + * spi_async_locked - version of spi_async with exclusive bus usage + * @spi: device with which data will be exchanged + * @message: describes the data transfers, including completion callback + * Context: any (irqs may be blocked, etc) + * + * This call may be used in_irq and other contexts which can't sleep, + * as well as from task contexts which can sleep. + * + * The completion callback is invoked in a context which can't sleep. + * Before that invocation, the value of message->status is undefined. + * When the callback is issued, message->status holds either zero (to + * indicate complete success) or a negative error code. After that + * callback returns, the driver which issued the transfer request may + * deallocate the associated memory; it's no longer in use by any SPI + * core or controller driver code. + * + * Note that although all messages to a spi_device are handled in + * FIFO order, messages may go to different devices in other orders. + * Some device might be higher priority, or have various "hard" access + * time requirements, for example. + * + * On detection of any fault during the transfer, processing of + * the entire message is aborted, and the device is deselected. + * Until returning from the associated message completion callback, + * no other spi_message queued to that device will be processed. + * (This rule applies equally to all the synchronous transfer calls, + * which are wrappers around this core asynchronous primitive.) + */ +int spi_async_locked(struct spi_device *spi, struct spi_message *message) +{ + struct spi_master *master = spi->master; + int ret; + unsigned long flags; + + spin_lock_irqsave(&master->bus_lock_spinlock, flags); + + ret = __spi_async(spi, message); + + spin_unlock_irqrestore(&master->bus_lock_spinlock, flags); + + return ret; + +} +EXPORT_SYMBOL_GPL(spi_async_locked); + /*-------------------------------------------------------------------------*/ @@ -742,6 +810,32 @@ static void spi_complete(void *arg) complete(arg); } +static int __spi_sync(struct spi_device *spi, struct spi_message *message, + int bus_locked) +{ + DECLARE_COMPLETION_ONSTACK(done); + int status; + struct spi_master *master = spi->master; + + message->complete = spi_complete; + message->context = &done; + + if (!bus_locked) + mutex_lock(&master->bus_lock_mutex); + + status = spi_async_locked(spi, message); + + if (!bus_locked) + mutex_unlock(&master->bus_lock_mutex); + + if (status == 0) { + wait_for_completion(&done); + status = message->status; + } + message->context = NULL; + return status; +} + /** * spi_sync - blocking/synchronous SPI data transfers * @spi: device with which data will be exchanged @@ -765,21 +859,86 @@ static void spi_complete(void *arg) */ int spi_sync(struct spi_device *spi, struct spi_message *message) { - DECLARE_COMPLETION_ONSTACK(done); - int status; - - message->complete = spi_complete; - message->context = &done; - status = spi_async(spi, message); - if (status == 0) { - wait_for_completion(&done); - status = message->status; - } - message->context = NULL; - return status; + return __spi_sync(spi, message, 0); } EXPORT_SYMBOL_GPL(spi_sync); +/** + * spi_sync_locked - version of spi_sync with exclusive bus usage + * @spi: device with which data will be exchanged + * @message: describes the data transfers + * Context: can sleep + * + * This call may only be used from a context that may sleep. The sleep + * is non-interruptible, and has no timeout. Low-overhead controller + * drivers may DMA directly into and out of the message buffers. + * + * This call should be used by drivers that require exclusive access to the + * SPI bus. It has to be preceeded by a spi_bus_lock call. The SPI bus must + * be released by a spi_bus_unlock call when the exclusive access is over. + * + * It returns zero on success, else a negative error code. + */ +int spi_sync_locked(struct spi_device *spi, struct spi_message *message) +{ + return __spi_sync(spi, message, 1); +} +EXPORT_SYMBOL_GPL(spi_sync_locked); + +/** + * spi_bus_lock - obtain a lock for exclusive SPI bus usage + * @master: SPI bus master that should be locked for exclusive bus access + * Context: can sleep + * + * This call may only be used from a context that may sleep. The sleep + * is non-interruptible, and has no timeout. + * + * This call should be used by drivers that require exclusive access to the + * SPI bus. The SPI bus must be released by a spi_bus_unlock call when the + * exclusive access is over. Data transfer must be done by spi_sync_locked + * and spi_async_locked calls when the SPI bus lock is held. + * + * It returns zero on success, else a negative error code. + */ +int spi_bus_lock(struct spi_master *master) +{ + unsigned long flags; + + mutex_lock(&master->bus_lock_mutex); + + spin_lock_irqsave(&master->bus_lock_spinlock, flags); + master->bus_lock_flag = 1; + spin_unlock_irqrestore(&master->bus_lock_spinlock, flags); + + /* mutex remains locked until spi_bus_unlock is called */ + + return 0; +} +EXPORT_SYMBOL_GPL(spi_bus_lock); + +/** + * spi_bus_unlock - release the lock for exclusive SPI bus usage + * @master: SPI bus master that was locked for exclusive bus access + * Context: can sleep + * + * This call may only be used from a context that may sleep. The sleep + * is non-interruptible, and has no timeout. + * + * This call releases an SPI bus lock previously obtained by an spi_bus_lock + * call. + * + * It returns zero on success, else a negative error code. + */ +int spi_bus_unlock(struct spi_master *master) +{ + master->bus_lock_flag = 0; + + mutex_unlock(&master->bus_lock_mutex); + + return 0; +} +EXPORT_SYMBOL_GPL(spi_bus_unlock); + /* portable code must never pass more than 32 bytes */ #define SPI_BUFSIZ max(32,SMP_CACHE_BYTES) diff --git a/drivers/spi/spi_bitbang.c b/drivers/spi/spi_bitbang.c index 5265330a528f..8b55724d5f39 100644 --- a/drivers/spi/spi_bitbang.c +++ b/drivers/spi/spi_bitbang.c @@ -259,7 +259,6 @@ static void bitbang_work(struct work_struct *work) struct spi_bitbang *bitbang = container_of(work, struct spi_bitbang, work); unsigned long flags; - int do_setup = -1; int (*setup_transfer)(struct spi_device *, struct spi_transfer *); @@ -275,6 +274,7 @@ static void bitbang_work(struct work_struct *work) unsigned tmp; unsigned cs_change; int status; + int do_setup = -1; m = container_of(bitbang->queue.next, struct spi_message, queue); @@ -307,6 +307,8 @@ static void bitbang_work(struct work_struct *work) status = setup_transfer(spi, t); if (status < 0) break; + if (do_setup == -1) + do_setup = 0; } /* set up default clock polarity, and activate chip; @@ -367,11 +369,6 @@ static void bitbang_work(struct work_struct *work) m->status = status; m->complete(m->context); - /* restore speed and wordsize if it was overridden */ - if (do_setup == 1) - setup_transfer(spi, NULL); - do_setup = 0; - /* normally deactivate chipselect ... unless no error and * cs_change has hinted that the next message will probably * be for this chip too. diff --git a/drivers/spi/spi_bitbang_txrx.h b/drivers/spi/spi_bitbang_txrx.h index fc033bbf9180..c16bf853c3eb 100644 --- a/drivers/spi/spi_bitbang_txrx.h +++ b/drivers/spi/spi_bitbang_txrx.h @@ -44,7 +44,7 @@ static inline u32 bitbang_txrx_be_cpha0(struct spi_device *spi, - unsigned nsecs, unsigned cpol, + unsigned nsecs, unsigned cpol, unsigned flags, u32 word, u8 bits) { /* if (cpol == 0) this is SPI_MODE_0; else this is SPI_MODE_2 */ @@ -53,7 +53,8 @@ bitbang_txrx_be_cpha0(struct spi_device *spi, for (word <<= (32 - bits); likely(bits); bits--) { /* setup MSB (to slave) on trailing edge */ - setmosi(spi, word & (1 << 31)); + if ((flags & SPI_MASTER_NO_TX) == 0) + setmosi(spi, word & (1 << 31)); spidelay(nsecs); /* T(setup) */ setsck(spi, !cpol); @@ -61,7 +62,8 @@ bitbang_txrx_be_cpha0(struct spi_device *spi, /* sample MSB (from slave) on leading edge */ word <<= 1; - word |= getmiso(spi); + if ((flags & SPI_MASTER_NO_RX) == 0) + word |= getmiso(spi); setsck(spi, cpol); } return word; @@ -69,7 +71,7 @@ bitbang_txrx_be_cpha0(struct spi_device *spi, static inline u32 bitbang_txrx_be_cpha1(struct spi_device *spi, - unsigned nsecs, unsigned cpol, + unsigned nsecs, unsigned cpol, unsigned flags, u32 word, u8 bits) { /* if (cpol == 0) this is SPI_MODE_1; else this is SPI_MODE_3 */ @@ -79,7 +81,8 @@ bitbang_txrx_be_cpha1(struct spi_device *spi, /* setup MSB (to slave) on leading edge */ setsck(spi, !cpol); - setmosi(spi, word & (1 << 31)); + if ((flags & SPI_MASTER_NO_TX) == 0) + setmosi(spi, word & (1 << 31)); spidelay(nsecs); /* T(setup) */ setsck(spi, cpol); @@ -87,7 +90,8 @@ bitbang_txrx_be_cpha1(struct spi_device *spi, /* sample MSB (from slave) on trailing edge */ word <<= 1; - word |= getmiso(spi); + if ((flags & SPI_MASTER_NO_RX) == 0) + word |= getmiso(spi); } return word; } diff --git a/drivers/spi/spi_butterfly.c b/drivers/spi/spi_butterfly.c index 8b5281281111..0d4ceba3b590 100644 --- a/drivers/spi/spi_butterfly.c +++ b/drivers/spi/spi_butterfly.c @@ -156,7 +156,7 @@ butterfly_txrx_word_mode0(struct spi_device *spi, unsigned nsecs, u32 word, u8 bits) { - return bitbang_txrx_be_cpha0(spi, nsecs, 0, word, bits); + return bitbang_txrx_be_cpha0(spi, nsecs, 0, 0, word, bits); } /*----------------------------------------------------------------------*/ diff --git a/drivers/spi/spi_gpio.c b/drivers/spi/spi_gpio.c index 7edbd5807e0e..e24a63498acb 100644 --- a/drivers/spi/spi_gpio.c +++ b/drivers/spi/spi_gpio.c @@ -146,25 +146,63 @@ static inline int getmiso(const struct spi_device *spi) static u32 spi_gpio_txrx_word_mode0(struct spi_device *spi, unsigned nsecs, u32 word, u8 bits) { - return bitbang_txrx_be_cpha0(spi, nsecs, 0, word, bits); + return bitbang_txrx_be_cpha0(spi, nsecs, 0, 0, word, bits); } static u32 spi_gpio_txrx_word_mode1(struct spi_device *spi, unsigned nsecs, u32 word, u8 bits) { - return bitbang_txrx_be_cpha1(spi, nsecs, 0, word, bits); + return bitbang_txrx_be_cpha1(spi, nsecs, 0, 0, word, bits); } static u32 spi_gpio_txrx_word_mode2(struct spi_device *spi, unsigned nsecs, u32 word, u8 bits) { - return bitbang_txrx_be_cpha0(spi, nsecs, 1, word, bits); + return bitbang_txrx_be_cpha0(spi, nsecs, 1, 0, word, bits); } static u32 spi_gpio_txrx_word_mode3(struct spi_device *spi, unsigned nsecs, u32 word, u8 bits) { - return bitbang_txrx_be_cpha1(spi, nsecs, 1, word, bits); + return bitbang_txrx_be_cpha1(spi, nsecs, 1, 0, word, bits); +} + +/* + * These functions do not call setmosi or getmiso if respective flag + * (SPI_MASTER_NO_RX or SPI_MASTER_NO_TX) is set, so they are safe to + * call when such pin is not present or defined in the controller. + * A separate set of callbacks is defined to get highest possible + * speed in the generic case (when both MISO and MOSI lines are + * available), as optimiser will remove the checks when argument is + * constant. + */ + +static u32 spi_gpio_spec_txrx_word_mode0(struct spi_device *spi, + unsigned nsecs, u32 word, u8 bits) +{ + unsigned flags = spi->master->flags; + return bitbang_txrx_be_cpha0(spi, nsecs, 0, flags, word, bits); +} + +static u32 spi_gpio_spec_txrx_word_mode1(struct spi_device *spi, + unsigned nsecs, u32 word, u8 bits) +{ + unsigned flags = spi->master->flags; + return bitbang_txrx_be_cpha1(spi, nsecs, 0, flags, word, bits); +} + +static u32 spi_gpio_spec_txrx_word_mode2(struct spi_device *spi, + unsigned nsecs, u32 word, u8 bits) +{ + unsigned flags = spi->master->flags; + return bitbang_txrx_be_cpha0(spi, nsecs, 1, flags, word, bits); +} + +static u32 spi_gpio_spec_txrx_word_mode3(struct spi_device *spi, + unsigned nsecs, u32 word, u8 bits) +{ + unsigned flags = spi->master->flags; + return bitbang_txrx_be_cpha1(spi, nsecs, 1, flags, word, bits); } /*----------------------------------------------------------------------*/ @@ -232,19 +270,30 @@ static int __init spi_gpio_alloc(unsigned pin, const char *label, bool is_in) } static int __init -spi_gpio_request(struct spi_gpio_platform_data *pdata, const char *label) +spi_gpio_request(struct spi_gpio_platform_data *pdata, const char *label, + u16 *res_flags) { int value; /* NOTE: SPI_*_GPIO symbols may reference "pdata" */ - value = spi_gpio_alloc(SPI_MOSI_GPIO, label, false); - if (value) - goto done; + if (SPI_MOSI_GPIO != SPI_GPIO_NO_MOSI) { + value = spi_gpio_alloc(SPI_MOSI_GPIO, label, false); + if (value) + goto done; + } else { + /* HW configuration without MOSI pin */ + *res_flags |= SPI_MASTER_NO_TX; + } - value = spi_gpio_alloc(SPI_MISO_GPIO, label, true); - if (value) - goto free_mosi; + if (SPI_MISO_GPIO != SPI_GPIO_NO_MISO) { + value = spi_gpio_alloc(SPI_MISO_GPIO, label, true); + if (value) + goto free_mosi; + } else { + /* HW configuration without MISO pin */ + *res_flags |= SPI_MASTER_NO_RX; + } value = spi_gpio_alloc(SPI_SCK_GPIO, label, false); if (value) @@ -253,9 +302,11 @@ spi_gpio_request(struct spi_gpio_platform_data *pdata, const char *label) goto done; free_miso: - gpio_free(SPI_MISO_GPIO); + if (SPI_MISO_GPIO != SPI_GPIO_NO_MISO) + gpio_free(SPI_MISO_GPIO); free_mosi: - gpio_free(SPI_MOSI_GPIO); + if (SPI_MOSI_GPIO != SPI_GPIO_NO_MOSI) + gpio_free(SPI_MOSI_GPIO); done: return value; } @@ -266,6 +317,7 @@ static int __init spi_gpio_probe(struct platform_device *pdev) struct spi_master *master; struct spi_gpio *spi_gpio; struct spi_gpio_platform_data *pdata; + u16 master_flags = 0; pdata = pdev->dev.platform_data; #ifdef GENERIC_BITBANG @@ -273,7 +325,7 @@ static int __init spi_gpio_probe(struct platform_device *pdev) return -ENODEV; #endif - status = spi_gpio_request(pdata, dev_name(&pdev->dev)); + status = spi_gpio_request(pdata, dev_name(&pdev->dev), &master_flags); if (status < 0) return status; @@ -289,6 +341,7 @@ static int __init spi_gpio_probe(struct platform_device *pdev) if (pdata) spi_gpio->pdata = *pdata; + master->flags = master_flags; master->bus_num = pdev->id; master->num_chipselect = SPI_N_CHIPSEL; master->setup = spi_gpio_setup; @@ -296,10 +349,18 @@ static int __init spi_gpio_probe(struct platform_device *pdev) spi_gpio->bitbang.master = spi_master_get(master); spi_gpio->bitbang.chipselect = spi_gpio_chipselect; - spi_gpio->bitbang.txrx_word[SPI_MODE_0] = spi_gpio_txrx_word_mode0; - spi_gpio->bitbang.txrx_word[SPI_MODE_1] = spi_gpio_txrx_word_mode1; - spi_gpio->bitbang.txrx_word[SPI_MODE_2] = spi_gpio_txrx_word_mode2; - spi_gpio->bitbang.txrx_word[SPI_MODE_3] = spi_gpio_txrx_word_mode3; + + if ((master_flags & (SPI_MASTER_NO_RX | SPI_MASTER_NO_RX)) == 0) { + spi_gpio->bitbang.txrx_word[SPI_MODE_0] = spi_gpio_txrx_word_mode0; + spi_gpio->bitbang.txrx_word[SPI_MODE_1] = spi_gpio_txrx_word_mode1; + spi_gpio->bitbang.txrx_word[SPI_MODE_2] = spi_gpio_txrx_word_mode2; + spi_gpio->bitbang.txrx_word[SPI_MODE_3] = spi_gpio_txrx_word_mode3; + } else { + spi_gpio->bitbang.txrx_word[SPI_MODE_0] = spi_gpio_spec_txrx_word_mode0; + spi_gpio->bitbang.txrx_word[SPI_MODE_1] = spi_gpio_spec_txrx_word_mode1; + spi_gpio->bitbang.txrx_word[SPI_MODE_2] = spi_gpio_spec_txrx_word_mode2; + spi_gpio->bitbang.txrx_word[SPI_MODE_3] = spi_gpio_spec_txrx_word_mode3; + } spi_gpio->bitbang.setup_transfer = spi_bitbang_setup_transfer; spi_gpio->bitbang.flags = SPI_CS_HIGH; @@ -307,8 +368,10 @@ static int __init spi_gpio_probe(struct platform_device *pdev) if (status < 0) { spi_master_put(spi_gpio->bitbang.master); gpio_free: - gpio_free(SPI_MISO_GPIO); - gpio_free(SPI_MOSI_GPIO); + if (SPI_MISO_GPIO != SPI_GPIO_NO_MISO) + gpio_free(SPI_MISO_GPIO); + if (SPI_MOSI_GPIO != SPI_GPIO_NO_MOSI) + gpio_free(SPI_MOSI_GPIO); gpio_free(SPI_SCK_GPIO); spi_master_put(master); } @@ -331,8 +394,10 @@ static int __exit spi_gpio_remove(struct platform_device *pdev) platform_set_drvdata(pdev, NULL); - gpio_free(SPI_MISO_GPIO); - gpio_free(SPI_MOSI_GPIO); + if (SPI_MISO_GPIO != SPI_GPIO_NO_MISO) + gpio_free(SPI_MISO_GPIO); + if (SPI_MOSI_GPIO != SPI_GPIO_NO_MOSI) + gpio_free(SPI_MOSI_GPIO); gpio_free(SPI_SCK_GPIO); return status; diff --git a/drivers/spi/spi_lm70llp.c b/drivers/spi/spi_lm70llp.c index 86fb7b5993db..7746a41ab6d6 100644 --- a/drivers/spi/spi_lm70llp.c +++ b/drivers/spi/spi_lm70llp.c @@ -191,7 +191,7 @@ static void lm70_chipselect(struct spi_device *spi, int value) */ static u32 lm70_txrx(struct spi_device *spi, unsigned nsecs, u32 word, u8 bits) { - return bitbang_txrx_be_cpha0(spi, nsecs, 0, word, bits); + return bitbang_txrx_be_cpha0(spi, nsecs, 0, 0, word, bits); } static void spi_lm70llp_attach(struct parport *p) diff --git a/drivers/spi/spi_s3c24xx_gpio.c b/drivers/spi/spi_s3c24xx_gpio.c index 8979a75dbd7b..be991359bf92 100644 --- a/drivers/spi/spi_s3c24xx_gpio.c +++ b/drivers/spi/spi_s3c24xx_gpio.c @@ -64,25 +64,25 @@ static inline u32 getmiso(struct spi_device *dev) static u32 s3c2410_spigpio_txrx_mode0(struct spi_device *spi, unsigned nsecs, u32 word, u8 bits) { - return bitbang_txrx_be_cpha0(spi, nsecs, 0, word, bits); + return bitbang_txrx_be_cpha0(spi, nsecs, 0, 0, word, bits); } static u32 s3c2410_spigpio_txrx_mode1(struct spi_device *spi, unsigned nsecs, u32 word, u8 bits) { - return bitbang_txrx_be_cpha1(spi, nsecs, 0, word, bits); + return bitbang_txrx_be_cpha1(spi, nsecs, 0, 0, word, bits); } static u32 s3c2410_spigpio_txrx_mode2(struct spi_device *spi, unsigned nsecs, u32 word, u8 bits) { - return bitbang_txrx_be_cpha0(spi, nsecs, 1, word, bits); + return bitbang_txrx_be_cpha0(spi, nsecs, 1, 0, word, bits); } static u32 s3c2410_spigpio_txrx_mode3(struct spi_device *spi, unsigned nsecs, u32 word, u8 bits) { - return bitbang_txrx_be_cpha1(spi, nsecs, 1, word, bits); + return bitbang_txrx_be_cpha1(spi, nsecs, 1, 0, word, bits); } diff --git a/drivers/spi/spi_sh_sci.c b/drivers/spi/spi_sh_sci.c index a511be7961a0..5c6439161199 100644 --- a/drivers/spi/spi_sh_sci.c +++ b/drivers/spi/spi_sh_sci.c @@ -83,25 +83,25 @@ static inline u32 getmiso(struct spi_device *dev) static u32 sh_sci_spi_txrx_mode0(struct spi_device *spi, unsigned nsecs, u32 word, u8 bits) { - return bitbang_txrx_be_cpha0(spi, nsecs, 0, word, bits); + return bitbang_txrx_be_cpha0(spi, nsecs, 0, 0, word, bits); } static u32 sh_sci_spi_txrx_mode1(struct spi_device *spi, unsigned nsecs, u32 word, u8 bits) { - return bitbang_txrx_be_cpha1(spi, nsecs, 0, word, bits); + return bitbang_txrx_be_cpha1(spi, nsecs, 0, 0, word, bits); } static u32 sh_sci_spi_txrx_mode2(struct spi_device *spi, unsigned nsecs, u32 word, u8 bits) { - return bitbang_txrx_be_cpha0(spi, nsecs, 1, word, bits); + return bitbang_txrx_be_cpha0(spi, nsecs, 1, 0, word, bits); } static u32 sh_sci_spi_txrx_mode3(struct spi_device *spi, unsigned nsecs, u32 word, u8 bits) { - return bitbang_txrx_be_cpha1(spi, nsecs, 1, word, bits); + return bitbang_txrx_be_cpha1(spi, nsecs, 1, 0, word, bits); } static void sh_sci_spi_chipselect(struct spi_device *dev, int value) diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h index af56071b06f9..ae0a5286f558 100644 --- a/include/linux/spi/spi.h +++ b/include/linux/spi/spi.h @@ -262,6 +262,13 @@ struct spi_master { #define SPI_MASTER_NO_RX BIT(1) /* can't do buffer read */ #define SPI_MASTER_NO_TX BIT(2) /* can't do buffer write */ + /* lock and mutex for SPI bus locking */ + spinlock_t bus_lock_spinlock; + struct mutex bus_lock_mutex; + + /* flag indicating that the SPI bus is locked for exclusive use */ + bool bus_lock_flag; + /* Setup mode and clock, etc (spi driver may call many times). * * IMPORTANT: this may be called when transfers to another @@ -542,6 +549,8 @@ static inline void spi_message_free(struct spi_message *m) extern int spi_setup(struct spi_device *spi); extern int spi_async(struct spi_device *spi, struct spi_message *message); +extern int spi_async_locked(struct spi_device *spi, + struct spi_message *message); /*---------------------------------------------------------------------------*/ @@ -551,6 +560,9 @@ extern int spi_async(struct spi_device *spi, struct spi_message *message); */ extern int spi_sync(struct spi_device *spi, struct spi_message *message); +extern int spi_sync_locked(struct spi_device *spi, struct spi_message *message); +extern int spi_bus_lock(struct spi_master *master); +extern int spi_bus_unlock(struct spi_master *master); /** * spi_write - SPI synchronous write diff --git a/include/linux/spi/spi_gpio.h b/include/linux/spi/spi_gpio.h index ca6782ee4b9f..369b3d7d5b95 100644 --- a/include/linux/spi/spi_gpio.h +++ b/include/linux/spi/spi_gpio.h @@ -29,11 +29,16 @@ * SPI_GPIO_NO_CHIPSELECT to the controller_data: * .controller_data = (void *) SPI_GPIO_NO_CHIPSELECT; * + * If the MISO or MOSI pin is not available then it should be set to + * SPI_GPIO_NO_MISO or SPI_GPIO_NO_MOSI. + * * If the bitbanged bus is later switched to a "native" controller, * that platform_device and controller_data should be removed. */ #define SPI_GPIO_NO_CHIPSELECT ((unsigned long)-1l) +#define SPI_GPIO_NO_MISO ((unsigned long)-1l) +#define SPI_GPIO_NO_MOSI ((unsigned long)-1l) /** * struct spi_gpio_platform_data - parameter for bitbanged SPI master