kernel@xxxxxxxxxxxxxxxx writes: > From: Martin Sperl <kernel@xxxxxxxxxxxxxxxx> > > Implements spi master driver for the 2 auxiliar spi devices > supported by the bcm2835 SOC. > > The driver does not implement native chip-selects but uses > framework provided aribtrary GPIO-chip-selects. > > Requires soc-bcm2835-aux enable api to enable/disable HW blocks. > > Signed-off-by: Martin Sperl <kernel@xxxxxxxxxxxxxxxx> > --- > drivers/spi/Kconfig | 12 + > drivers/spi/Makefile | 1 + > drivers/spi/spi-bcm2835aux.c | 514 ++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 527 insertions(+) > create mode 100644 drivers/spi/spi-bcm2835aux.c > > Changelog: > v4->v5: added error-handling and deferred probing support > moved change to default-config to a separate patch > fixed Kconfig to add the correct dependency Review comments as a diff, so you can git-am and squash them in if you like. If you take them all, you can add "Acked-by: Eric Anholt <eric@xxxxxxxxxx>". I didn't know anything about SPI before tonight, but I've looked through what you did and it looks solid when compared to the hardware docs I've got. The only functional comment I had that's not in my diff is that you could probably reduce the transfer overhead by knowing that there are 4 dwords in the transfer and receive FIFOs, so I think you could write more before checking if you had to stop. From e082c3b5ea32d3eb1a40b7f9b5a822ba307cf886 Mon Sep 17 00:00:00 2001 From: Eric Anholt <eric@xxxxxxxxxx> Date: Tue, 8 Sep 2015 17:51:08 -0700 Subject: [PATCH] spi: Changes for Martin's aux spi driver. The intention is for these to be review fixes squashed into his commit of the driver. - Reset has to happen before the clock gate is disabled, since register writes wouldn't take effect. - Typo fixes. - Dropped unnecessary regs/defines. - Dropped custom clock enable/disable, assuming we use the aux clock driver instead. Signed-off-by: Eric Anholt <eric@xxxxxxxxxx> --- drivers/spi/Kconfig | 5 ++--- drivers/spi/spi-bcm2835aux.c | 45 ++++++-------------------------------------- 2 files changed, 8 insertions(+), 42 deletions(-) diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index cdb3dba..20854d4 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -89,16 +89,15 @@ config SPI_BCM2835 not supported. config SPI_BCM2835AUX - tristate "BCM2835 SPI auxiliar controller" + tristate "BCM2835 SPI auxiliary controller" depends on ARCH_BCM2835 || COMPILE_TEST depends on GPIOLIB - select SOC_BCM2835_AUX help This selects a driver for the Broadcom BCM2835 SPI aux master. The BCM2835 contains two types of SPI master controller; the "universal SPI master", and the regular SPI controller. - This driver is for the universal/auxiliar SPI controller. + This driver is for the universal/auxiliary SPI controller. config SPI_BFIN5XX tristate "SPI controller driver for ADI Blackfin5xx" diff --git a/drivers/spi/spi-bcm2835aux.c b/drivers/spi/spi-bcm2835aux.c index d968647..3451ecb 100644 --- a/drivers/spi/spi-bcm2835aux.c +++ b/drivers/spi/spi-bcm2835aux.c @@ -1,5 +1,5 @@ /* - * Driver for Broadcom BCM2835 SPI Controllers + * Driver for Broadcom BCM2835 auxiliary SPI Controllers * * the driver does not rely on the native chipselects at all * but only uses the gpio type chipselects @@ -26,7 +26,6 @@ #include <linux/interrupt.h> #include <linux/io.h> #include <linux/kernel.h> -#include <linux/soc/bcm/bcm2835-aux.h> #include <linux/module.h> #include <linux/of.h> #include <linux/of_address.h> @@ -38,27 +37,10 @@ #include <linux/spinlock.h> /* - * shared aux registers between spi1/spi2 and uart1 - * - * these defines could go to a separate module if needed - * so that it can also get used with the uart1 implementation - * when it materializes. - */ - -/* the AUX register offsets */ -#define BCM2835_AUX_IRQ 0x00 -#define BCM2835_AUX_ENABLE 0x04 - -/* the AUX Bitfield identical for both register */ -#define BCM2835_AUX_BIT_UART 0x00000001 -#define BCM2835_AUX_BIT_SPI1 0x00000002 -#define BCM2835_AUX_BIT_SPI2 0x00000004 - -/* * spi register defines * * note there is garbage in the "official" documentation, - * so somedata taken from the file: + * so some data is taken from the file: * brcm_usrlib/dag/vmcsx/vcinclude/bcm2708_chip/aux_io.h * inside of: * http://www.broadcom.com/docs/support/videocore/Brcm_Android_ICS_Graphics_Stack.tar.gz @@ -113,9 +95,6 @@ #define BCM2835_AUX_SPI_MODE_BITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH \ | SPI_NO_CS) -#define DRV_NAME "spi-bcm2835aux" -#define ENABLE_PROPERTY "brcm,aux-enable" - struct bcm2835aux_spi { void __iomem *regs; struct clk *clk; @@ -450,26 +429,17 @@ static int bcm2835aux_spi_probe(struct platform_device *pdev) goto out_clk_disable; } - /* enable HW block */ - err = bcm2835aux_enable(&pdev->dev, ENABLE_PROPERTY); - if (err) { - dev_err(&pdev->dev, "could not enable aux: %d\n", err); - goto out_clk_disable; - } - /* reset SPI-HW block */ bcm2835aux_spi_reset_hw(bs); err = devm_spi_register_master(&pdev->dev, master); if (err) { dev_err(&pdev->dev, "could not register SPI master: %d\n", err); - goto out_hw_disable; + goto out_clk_disable; } return 0; -out_hw_disable: - bcm2835aux_disable(&pdev->dev, ENABLE_PROPERTY); out_clk_disable: clk_disable_unprepare(bs->clk); out_master_put: @@ -482,13 +452,10 @@ static int bcm2835aux_spi_remove(struct platform_device *pdev) struct spi_master *master = platform_get_drvdata(pdev); struct bcm2835aux_spi *bs = spi_master_get_devdata(master); - /* Clear FIFOs, and disable the HW block */ - clk_disable_unprepare(bs->clk); - bcm2835aux_spi_reset_hw(bs); - /* disable HW block */ - bcm2835aux_disable(&pdev->dev, ENABLE_PROPERTY); + /* Clear FIFOs, and disable the HW block */ + clk_disable_unprepare(bs->clk); return 0; } @@ -501,7 +468,7 @@ MODULE_DEVICE_TABLE(of, bcm2835aux_spi_match); static struct platform_driver bcm2835aux_spi_driver = { .driver = { - .name = DRV_NAME, + .name = "spi-bcm2835aux", .of_match_table = bcm2835aux_spi_match, }, .probe = bcm2835aux_spi_probe, -- 2.1.4
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