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path: root/drivers/spi/spi-bcm2835.c
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2013-08-22spi: bcm2835: Add spi_master_get() call to prevent use after freeAxel Lin
The call to spi_unregister_master results in device memory being freed, it must no longer be accessed afterwards. Thus call spi_master_get() to get an extra reference to the device and call spi_master_put() only after the last access to device data. Note, current code has an extra spi_master_put() call in bcm2835_spi_remove(). Thus this patch just adds an spi_master_get() to balance the reference count. Signed-off-by: Axel Lin <axel.lin@ingics.com> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-05spi: bcm2835: Use SPI_BPW_MASK macro for bits_per_word_mask settingAxel Lin
We have a SPI_BPW_MASK macro defined in spi.h, use it instead of open-coded. Signed-off-by: Axel Lin <axel.lin@ingics.com> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-07-24spi: bcm2835: don't check resource with devm_ioremap_resourceWolfram Sang
devm_ioremap_resource does sanity checks on the given resource. No need to duplicate this in the driver. Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-05-13spi: bmc2835: use devm_ioremap_resource()Laurent Navet
Replace a call to deprecated devm_request_and_ioremap by devm_ioremap_resource. Found with coccicheck and this semantic patch: scripts/coccinelle/api/devm_request_and_ioremap.cocci. Signed-off-by: Laurent Navet <laurent.navet@gmail.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-04-01spi: bcm2835: make use of new bits_per_word_mask core featureStephen Warren
This driver only supports bits_per_word==8, so inform the SPI core of this. Remove all the open-coded validation that's no longer needed. Signed-off-by: Stephen Warren <swarren@wwwdotorg.org> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-03-12spi: add driver for BCM2835Chris Boot
The BCM2835 contains two forms of SPI master controller (one known simply as SPI0, and the other known as the "Universal SPI Master", in the auxilliary block) and one form of SPI slave controller. This patch adds support for the SPI0 controller. This driver is taken from Chris Boot's repository at git://github.com/bootc/linux.git rpi-linear as of commit 6de2905 "spi-bcm2708: fix printf with spurious %s". In the first SPI-related commit there, Chris wrote: Thanks to csoutreach / A Robinson for his driver which I used as an inspiration. You can find his version here: http://piface.openlx.org.uk/raspberry-pi-spi-kernel-driver-available-for Changes made during upstreaming: * Renamed bcm2708 to bcm2835 as per upstream naming for this SoC. * Removed support for brcm,realtime property. * Increased transfer timeout to 30 seconds. * Return IRQ_NONE from the IRQ handler if no interrupt was handled. * Disable TA (Transfer Active) and clear FIFOs on a transfer timeout. * Wrote device tree binding documentation. * Request unnamed clock rather than "sys_pclk"; the DT will provide the correct clock. * Assume that tfr->speed_hz and tfr->bits_per_word are always set in bcm2835_spi_start_transfer(), bcm2835_spi_transfer_one(), so no need to check spi->speed_hz or tft->bits_per_word. * Re-ordered probe() to remove the need for temporary variables. * Call clk_disable_unprepare() rather than just clk_unprepare() on probe() failure. * Don't use devm_request_irq(), to ensure that the IRQ doesn't fire after we've torn down the device, but not unhooked the IRQ. * Moved probe()'s call to clk_prepare_enable() so we can be sure the clock is enabled if the IRQ handler fires immediately. * Remove redundant checks from bcm2835_spi_check_transfer() and bcm2835_spi_setup(). * Re-ordered IRQ handler to check for RXR before DONE. Added comments to ISR. * Removed empty prepare/unprepare implementations. * Removed use of devinit/devexit. * Added BCM2835_ prefix to defines. Signed-off-by: Chris Boot <bootc@bootc.net> Signed-off-by: Stephen Warren <swarren@wwwdotorg.org> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>