From 94c69f765f1b4a658d96905ec59928e3e3e07e6a Mon Sep 17 00:00:00 2001 From: Axel Lin Date: Tue, 10 Sep 2013 15:43:41 +0800 Subject: spi: bitbang: Let spi_bitbang_start() take a reference to master Many drivers that use bitbang library have a leak on probe error paths. This is because once a spi_master_get() call succeeds, we need an additional spi_master_put() call to free the memory. Fix this issue by moving the code taking a reference to master to spi_bitbang_start(), so spi_bitbang_start() will take a reference to master on success. With this change, the caller is responsible for calling spi_bitbang_stop() to decrement the reference and spi_master_put() as counterpart of spi_alloc_master() to prevent a memory leak. So now we have below patten for drivers using bitbang library: probe: spi_alloc_master -> Init reference count to 1 spi_bitbang_start -> Increment reference count remove: spi_bitbang_stop -> Decrement reference count spi_master_put -> Decrement reference count (reference count reaches 0) Fixup all users accordingly. Signed-off-by: Axel Lin Suggested-by: Uwe Kleine-Koenig Acked-by: Uwe Kleine-Koenig Signed-off-by: Mark Brown --- drivers/spi/spi-altera.c | 2 +- drivers/spi/spi-ath79.c | 2 +- drivers/spi/spi-au1550.c | 2 +- drivers/spi/spi-bitbang.c | 12 +++++++++++- drivers/spi/spi-butterfly.c | 2 +- drivers/spi/spi-davinci.c | 10 ++++------ drivers/spi/spi-efm32.c | 2 +- drivers/spi/spi-fsl-dspi.c | 2 +- drivers/spi/spi-gpio.c | 5 ++--- drivers/spi/spi-imx.c | 2 +- drivers/spi/spi-lm70llp.c | 2 +- drivers/spi/spi-nuc900.c | 3 +-- drivers/spi/spi-oc-tiny.c | 2 +- drivers/spi/spi-ppc4xx.c | 3 ++- drivers/spi/spi-s3c24xx.c | 2 +- drivers/spi/spi-sh-sci.c | 2 +- drivers/spi/spi-sirf.c | 2 +- drivers/spi/spi-xilinx.c | 2 +- 18 files changed, 33 insertions(+), 26 deletions(-) (limited to 'drivers') diff --git a/drivers/spi/spi-altera.c b/drivers/spi/spi-altera.c index 9a64c3fee218..595b62cb545d 100644 --- a/drivers/spi/spi-altera.c +++ b/drivers/spi/spi-altera.c @@ -219,7 +219,7 @@ static int altera_spi_probe(struct platform_device *pdev) platform_set_drvdata(pdev, hw); /* setup the state for the bitbang driver */ - hw->bitbang.master = spi_master_get(master); + hw->bitbang.master = master; if (!hw->bitbang.master) return err; hw->bitbang.chipselect = altera_spi_chipsel; diff --git a/drivers/spi/spi-ath79.c b/drivers/spi/spi-ath79.c index 37bad952ab38..821bf7ac218d 100644 --- a/drivers/spi/spi-ath79.c +++ b/drivers/spi/spi-ath79.c @@ -231,7 +231,7 @@ static int ath79_spi_probe(struct platform_device *pdev) master->num_chipselect = pdata->num_chipselect; } - sp->bitbang.master = spi_master_get(master); + sp->bitbang.master = master; sp->bitbang.chipselect = ath79_spi_chipselect; sp->bitbang.txrx_word[SPI_MODE_0] = ath79_spi_txrx_mode0; sp->bitbang.setup_transfer = spi_bitbang_setup_transfer; diff --git a/drivers/spi/spi-au1550.c b/drivers/spi/spi-au1550.c index 1d00d9b397dd..e06400a3a719 100644 --- a/drivers/spi/spi-au1550.c +++ b/drivers/spi/spi-au1550.c @@ -775,7 +775,7 @@ static int au1550_spi_probe(struct platform_device *pdev) hw = spi_master_get_devdata(master); - hw->master = spi_master_get(master); + hw->master = master; hw->pdata = dev_get_platdata(&pdev->dev); hw->dev = &pdev->dev; diff --git a/drivers/spi/spi-bitbang.c b/drivers/spi/spi-bitbang.c index 8c11355dec23..0056623dfc6b 100644 --- a/drivers/spi/spi-bitbang.c +++ b/drivers/spi/spi-bitbang.c @@ -414,10 +414,16 @@ static int spi_bitbang_unprepare_hardware(struct spi_master *spi) * This routine registers the spi_master, which will process requests in a * dedicated task, keeping IRQs unblocked most of the time. To stop * processing those requests, call spi_bitbang_stop(). + * + * On success, this routine will take a reference to master. The caller is + * responsible for calling spi_bitbang_stop() to decrement the reference and + * spi_master_put() as counterpart of spi_alloc_master() to prevent a memory + * leak. */ int spi_bitbang_start(struct spi_bitbang *bitbang) { struct spi_master *master = bitbang->master; + int ret; if (!master || !bitbang->chipselect) return -EINVAL; @@ -449,7 +455,11 @@ int spi_bitbang_start(struct spi_bitbang *bitbang) /* driver may get busy before register() returns, especially * if someone registered boardinfo for devices */ - return spi_register_master(master); + ret = spi_register_master(spi_master_get(master)); + if (ret) + spi_master_put(master); + + return 0; } EXPORT_SYMBOL_GPL(spi_bitbang_start); diff --git a/drivers/spi/spi-butterfly.c b/drivers/spi/spi-butterfly.c index 5ed08e537433..b1ecea2d76b3 100644 --- a/drivers/spi/spi-butterfly.c +++ b/drivers/spi/spi-butterfly.c @@ -225,7 +225,7 @@ static void butterfly_attach(struct parport *p) master->bus_num = 42; master->num_chipselect = 2; - pp->bitbang.master = spi_master_get(master); + pp->bitbang.master = master; pp->bitbang.chipselect = butterfly_chipselect; pp->bitbang.txrx_word[SPI_MODE_0] = butterfly_txrx_word_mode0; diff --git a/drivers/spi/spi-davinci.c b/drivers/spi/spi-davinci.c index 8fbfe2483ffd..af2bb73d0168 100644 --- a/drivers/spi/spi-davinci.c +++ b/drivers/spi/spi-davinci.c @@ -916,7 +916,7 @@ static int davinci_spi_probe(struct platform_device *pdev) if (ret) goto unmap_io; - dspi->bitbang.master = spi_master_get(master); + dspi->bitbang.master = master; if (dspi->bitbang.master == NULL) { ret = -ENODEV; goto irq_free; @@ -925,7 +925,7 @@ static int davinci_spi_probe(struct platform_device *pdev) dspi->clk = clk_get(&pdev->dev, NULL); if (IS_ERR(dspi->clk)) { ret = -ENODEV; - goto put_master; + goto irq_free; } clk_prepare_enable(dspi->clk); @@ -1015,8 +1015,6 @@ free_dma: free_clk: clk_disable_unprepare(dspi->clk); clk_put(dspi->clk); -put_master: - spi_master_put(master); irq_free: free_irq(dspi->irq, dspi); unmap_io: @@ -1024,7 +1022,7 @@ unmap_io: release_region: release_mem_region(dspi->pbase, resource_size(r)); free_master: - kfree(master); + spi_master_put(master); err: return ret; } @@ -1051,11 +1049,11 @@ static int davinci_spi_remove(struct platform_device *pdev) clk_disable_unprepare(dspi->clk); clk_put(dspi->clk); - spi_master_put(master); free_irq(dspi->irq, dspi); iounmap(dspi->base); r = platform_get_resource(pdev, IORESOURCE_MEM, 0); release_mem_region(dspi->pbase, resource_size(r)); + spi_master_put(master); return 0; } diff --git a/drivers/spi/spi-efm32.c b/drivers/spi/spi-efm32.c index 7d84418a01d8..d428a40778c1 100644 --- a/drivers/spi/spi-efm32.c +++ b/drivers/spi/spi-efm32.c @@ -347,7 +347,7 @@ static int efm32_spi_probe(struct platform_device *pdev) ddata = spi_master_get_devdata(master); - ddata->bitbang.master = spi_master_get(master); + ddata->bitbang.master = master; ddata->bitbang.chipselect = efm32_spi_chipselect; ddata->bitbang.setup_transfer = efm32_spi_setup_transfer; ddata->bitbang.txrx_bufs = efm32_spi_txrx_bufs; diff --git a/drivers/spi/spi-fsl-dspi.c b/drivers/spi/spi-fsl-dspi.c index 6cd07d13ecab..d338b6722255 100644 --- a/drivers/spi/spi-fsl-dspi.c +++ b/drivers/spi/spi-fsl-dspi.c @@ -450,7 +450,7 @@ static int dspi_probe(struct platform_device *pdev) dspi = spi_master_get_devdata(master); dspi->pdev = pdev; - dspi->bitbang.master = spi_master_get(master); + dspi->bitbang.master = master; dspi->bitbang.chipselect = dspi_chipselect; dspi->bitbang.setup_transfer = dspi_setup_transfer; dspi->bitbang.txrx_bufs = dspi_txrx_transfer; diff --git a/drivers/spi/spi-gpio.c b/drivers/spi/spi-gpio.c index 68b69fec13a9..14c01b44ca7a 100644 --- a/drivers/spi/spi-gpio.c +++ b/drivers/spi/spi-gpio.c @@ -467,7 +467,7 @@ static int spi_gpio_probe(struct platform_device *pdev) } #endif - spi_gpio->bitbang.master = spi_master_get(master); + spi_gpio->bitbang.master = master; spi_gpio->bitbang.chipselect = spi_gpio_chipselect; if ((master_flags & (SPI_MASTER_NO_TX | SPI_MASTER_NO_RX)) == 0) { @@ -486,7 +486,6 @@ static int spi_gpio_probe(struct platform_device *pdev) status = spi_bitbang_start(&spi_gpio->bitbang); if (status < 0) { - spi_master_put(spi_gpio->bitbang.master); gpio_free: if (SPI_MISO_GPIO != SPI_GPIO_NO_MISO) gpio_free(SPI_MISO_GPIO); @@ -510,13 +509,13 @@ static int spi_gpio_remove(struct platform_device *pdev) /* stop() unregisters child devices too */ status = spi_bitbang_stop(&spi_gpio->bitbang); - spi_master_put(spi_gpio->bitbang.master); 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(spi_gpio->bitbang.master); return status; } diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c index 15323d8bd9cf..02d9f468b2b6 100644 --- a/drivers/spi/spi-imx.c +++ b/drivers/spi/spi-imx.c @@ -786,7 +786,7 @@ static int spi_imx_probe(struct platform_device *pdev) master->num_chipselect = num_cs; spi_imx = spi_master_get_devdata(master); - spi_imx->bitbang.master = spi_master_get(master); + spi_imx->bitbang.master = master; for (i = 0; i < master->num_chipselect; i++) { int cs_gpio = of_get_named_gpio(np, "cs-gpios", i); diff --git a/drivers/spi/spi-lm70llp.c b/drivers/spi/spi-lm70llp.c index 0759b5db9883..41c5765be746 100644 --- a/drivers/spi/spi-lm70llp.c +++ b/drivers/spi/spi-lm70llp.c @@ -222,7 +222,7 @@ static void spi_lm70llp_attach(struct parport *p) /* * SPI and bitbang hookup. */ - pp->bitbang.master = spi_master_get(master); + pp->bitbang.master = master; pp->bitbang.chipselect = lm70_chipselect; pp->bitbang.txrx_word[SPI_MODE_0] = lm70_txrx; pp->bitbang.flags = SPI_3WIRE; diff --git a/drivers/spi/spi-nuc900.c b/drivers/spi/spi-nuc900.c index 47a68b43bcd5..e0c32bc69ee2 100644 --- a/drivers/spi/spi-nuc900.c +++ b/drivers/spi/spi-nuc900.c @@ -349,7 +349,7 @@ static int nuc900_spi_probe(struct platform_device *pdev) } hw = spi_master_get_devdata(master); - hw->master = spi_master_get(master); + hw->master = master; hw->pdata = dev_get_platdata(&pdev->dev); hw->dev = &pdev->dev; @@ -435,7 +435,6 @@ err_iomap: kfree(hw->ioarea); err_pdata: spi_master_put(hw->master); - err_nomem: return err; } diff --git a/drivers/spi/spi-oc-tiny.c b/drivers/spi/spi-oc-tiny.c index 333cb1badcd7..91c668596202 100644 --- a/drivers/spi/spi-oc-tiny.c +++ b/drivers/spi/spi-oc-tiny.c @@ -306,7 +306,7 @@ static int tiny_spi_probe(struct platform_device *pdev) platform_set_drvdata(pdev, hw); /* setup the state for the bitbang driver */ - hw->bitbang.master = spi_master_get(master); + hw->bitbang.master = master; if (!hw->bitbang.master) return err; hw->bitbang.setup_transfer = tiny_spi_setup_transfer; diff --git a/drivers/spi/spi-ppc4xx.c b/drivers/spi/spi-ppc4xx.c index 0ee53c25ba58..c57740bb70d3 100644 --- a/drivers/spi/spi-ppc4xx.c +++ b/drivers/spi/spi-ppc4xx.c @@ -396,7 +396,7 @@ static int spi_ppc4xx_of_probe(struct platform_device *op) master->dev.of_node = np; platform_set_drvdata(op, master); hw = spi_master_get_devdata(master); - hw->master = spi_master_get(master); + hw->master = master; hw->dev = dev; init_completion(&hw->done); @@ -558,6 +558,7 @@ static int spi_ppc4xx_of_remove(struct platform_device *op) free_irq(hw->irqnum, hw); iounmap(hw->regs); free_gpios(hw); + spi_master_put(master); return 0; } diff --git a/drivers/spi/spi-s3c24xx.c b/drivers/spi/spi-s3c24xx.c index ce318d95a6ee..c9cfdfaf7523 100644 --- a/drivers/spi/spi-s3c24xx.c +++ b/drivers/spi/spi-s3c24xx.c @@ -524,7 +524,7 @@ static int s3c24xx_spi_probe(struct platform_device *pdev) hw = spi_master_get_devdata(master); memset(hw, 0, sizeof(struct s3c24xx_spi)); - hw->master = spi_master_get(master); + hw->master = master; hw->pdata = pdata = dev_get_platdata(&pdev->dev); hw->dev = &pdev->dev; diff --git a/drivers/spi/spi-sh-sci.c b/drivers/spi/spi-sh-sci.c index 8eefeb6007df..38eb24df796c 100644 --- a/drivers/spi/spi-sh-sci.c +++ b/drivers/spi/spi-sh-sci.c @@ -133,7 +133,7 @@ static int sh_sci_spi_probe(struct platform_device *dev) sp->info = dev_get_platdata(&dev->dev); /* setup spi bitbang adaptor */ - sp->bitbang.master = spi_master_get(master); + sp->bitbang.master = master; sp->bitbang.master->bus_num = sp->info->bus_num; sp->bitbang.master->num_chipselect = sp->info->num_chipselect; sp->bitbang.chipselect = sh_sci_spi_chipselect; diff --git a/drivers/spi/spi-sirf.c b/drivers/spi/spi-sirf.c index a1f21b747733..592b4aff651f 100644 --- a/drivers/spi/spi-sirf.c +++ b/drivers/spi/spi-sirf.c @@ -632,7 +632,7 @@ static int spi_sirfsoc_probe(struct platform_device *pdev) if (ret) goto free_master; - sspi->bitbang.master = spi_master_get(master); + sspi->bitbang.master = master; sspi->bitbang.chipselect = spi_sirfsoc_chipselect; sspi->bitbang.setup_transfer = spi_sirfsoc_setup_transfer; sspi->bitbang.txrx_bufs = spi_sirfsoc_transfer; diff --git a/drivers/spi/spi-xilinx.c b/drivers/spi/spi-xilinx.c index 0bf1b2c457a1..ec3a83f52ea2 100644 --- a/drivers/spi/spi-xilinx.c +++ b/drivers/spi/spi-xilinx.c @@ -372,7 +372,7 @@ static int xilinx_spi_probe(struct platform_device *pdev) master->mode_bits = SPI_CPOL | SPI_CPHA; xspi = spi_master_get_devdata(master); - xspi->bitbang.master = spi_master_get(master); + xspi->bitbang.master = master; xspi->bitbang.chipselect = xilinx_spi_chipselect; xspi->bitbang.setup_transfer = xilinx_spi_setup_transfer; xspi->bitbang.txrx_bufs = xilinx_spi_txrx_bufs; -- cgit v1.2.3