From 42c5d52f2bbf68add2d7a6982753993e0c75a119 Mon Sep 17 00:00:00 2001 From: Richard Zhao Date: Tue, 15 Nov 2011 14:47:56 +0800 Subject: [PATCH 01/12] clk: add helper functions clk_prepare_enable and clk_disable_unprepare It's for migrating to generic clk framework API. The helper functions help cases clk_enable/clk_disable is used in non-atomic context. For example, Call clk_enable in probe and clk_disable in remove. Signed-off-by: Richard Zhao Signed-off-by: Sascha Hauer Signed-off-by: Shawn Guo Cc: Russell King Acked-by: Marek Vasut --- include/linux/clk.h | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/include/linux/clk.h b/include/linux/clk.h index 7213b52b2c0..b9d46fa154b 100644 --- a/include/linux/clk.h +++ b/include/linux/clk.h @@ -107,6 +107,28 @@ static inline void clk_unprepare(struct clk *clk) } #endif +/* clk_prepare_enable helps cases using clk_enable in non-atomic context. */ +static inline int clk_prepare_enable(struct clk *clk) +{ + int ret; + + ret = clk_prepare(clk); + if (ret) + return ret; + ret = clk_enable(clk); + if (ret) + clk_unprepare(clk); + + return ret; +} + +/* clk_disable_unprepare helps cases using clk_disable in non-atomic context. */ +static inline void clk_disable_unprepare(struct clk *clk) +{ + clk_disable(clk); + clk_unprepare(clk); +} + /** * clk_get_rate - obtain the current clock rate (in Hz) for a clock source. * This is only valid once the clock source has been enabled. From ae68f7af05dbce25889ab10b302fba927dcdb295 Mon Sep 17 00:00:00 2001 From: Shawn Guo Date: Tue, 20 Dec 2011 13:50:11 +0800 Subject: [PATCH 02/12] ARM: mxs: convert platform code to clk_prepare/clk_unprepare The patch converts mxs platform code to clk_prepare/clk_unprepare by using helper functions clk_prepare_enable/clk_disable_unprepare. Signed-off-by: Richard Zhao Signed-off-by: Shawn Guo --- arch/arm/mach-mxs/clock-mx23.c | 10 +++++----- arch/arm/mach-mxs/clock-mx28.c | 10 +++++----- arch/arm/mach-mxs/clock.c | 2 +- arch/arm/mach-mxs/mach-mx28evk.c | 2 +- arch/arm/mach-mxs/system.c | 2 +- arch/arm/mach-mxs/timer.c | 2 +- 6 files changed, 14 insertions(+), 14 deletions(-) diff --git a/arch/arm/mach-mxs/clock-mx23.c b/arch/arm/mach-mxs/clock-mx23.c index 0163b6d8377..e12e11231dc 100644 --- a/arch/arm/mach-mxs/clock-mx23.c +++ b/arch/arm/mach-mxs/clock-mx23.c @@ -545,11 +545,11 @@ int __init mx23_clocks_init(void) */ clk_set_parent(&ssp_clk, &ref_io_clk); - clk_enable(&cpu_clk); - clk_enable(&hbus_clk); - clk_enable(&xbus_clk); - clk_enable(&emi_clk); - clk_enable(&uart_clk); + clk_prepare_enable(&cpu_clk); + clk_prepare_enable(&hbus_clk); + clk_prepare_enable(&xbus_clk); + clk_prepare_enable(&emi_clk); + clk_prepare_enable(&uart_clk); clkdev_add_table(lookups, ARRAY_SIZE(lookups)); diff --git a/arch/arm/mach-mxs/clock-mx28.c b/arch/arm/mach-mxs/clock-mx28.c index da6e4aad177..f85f1f5b3e1 100644 --- a/arch/arm/mach-mxs/clock-mx28.c +++ b/arch/arm/mach-mxs/clock-mx28.c @@ -775,11 +775,11 @@ int __init mx28_clocks_init(void) clk_set_parent(&ssp0_clk, &ref_io0_clk); clk_set_parent(&ssp1_clk, &ref_io0_clk); - clk_enable(&cpu_clk); - clk_enable(&hbus_clk); - clk_enable(&xbus_clk); - clk_enable(&emi_clk); - clk_enable(&uart_clk); + clk_prepare_enable(&cpu_clk); + clk_prepare_enable(&hbus_clk); + clk_prepare_enable(&xbus_clk); + clk_prepare_enable(&emi_clk); + clk_prepare_enable(&uart_clk); clk_set_parent(&lcdif_clk, &ref_pix_clk); clk_set_parent(&saif0_clk, &pll0_clk); diff --git a/arch/arm/mach-mxs/clock.c b/arch/arm/mach-mxs/clock.c index a7093c88e6a..755eec0b5a8 100644 --- a/arch/arm/mach-mxs/clock.c +++ b/arch/arm/mach-mxs/clock.c @@ -166,7 +166,7 @@ int clk_set_parent(struct clk *clk, struct clk *parent) return ret; if (clk->usecount) - clk_enable(parent); + clk_prepare_enable(parent); mutex_lock(&clocks_mutex); ret = clk->set_parent(clk, parent); diff --git a/arch/arm/mach-mxs/mach-mx28evk.c b/arch/arm/mach-mxs/mach-mx28evk.c index 064ec5abaa5..6b9e83e6e89 100644 --- a/arch/arm/mach-mxs/mach-mx28evk.c +++ b/arch/arm/mach-mxs/mach-mx28evk.c @@ -228,7 +228,7 @@ static void __init mx28evk_fec_reset(void) /* Enable fec phy clock */ clk = clk_get_sys("pll2", NULL); if (!IS_ERR(clk)) - clk_enable(clk); + clk_prepare_enable(clk); /* Power up fec phy */ ret = gpio_request(MX28EVK_FEC_PHY_POWER, "fec-phy-power"); diff --git a/arch/arm/mach-mxs/system.c b/arch/arm/mach-mxs/system.c index 20ec3bddf7c..9760a1285e0 100644 --- a/arch/arm/mach-mxs/system.c +++ b/arch/arm/mach-mxs/system.c @@ -66,7 +66,7 @@ static int __init mxs_arch_reset_init(void) clk = clk_get_sys("rtc", NULL); if (!IS_ERR(clk)) - clk_enable(clk); + clk_prepare_enable(clk); return 0; } diff --git a/arch/arm/mach-mxs/timer.c b/arch/arm/mach-mxs/timer.c index cace0d2e5a5..564a63279f1 100644 --- a/arch/arm/mach-mxs/timer.c +++ b/arch/arm/mach-mxs/timer.c @@ -245,7 +245,7 @@ static int __init mxs_clocksource_init(struct clk *timer_clk) void __init mxs_timer_init(struct clk *timer_clk, int irq) { - clk_enable(timer_clk); + clk_prepare_enable(timer_clk); /* * Initialize timers to a known state From 0ebafefcaa7a383b728d977a718e23e69ce84050 Mon Sep 17 00:00:00 2001 From: Richard Zhao Date: Tue, 15 Nov 2011 14:48:07 +0800 Subject: [PATCH 03/12] net: fec: add clk_prepare/clk_unprepare It's for migrating to generic clk framework API. Signed-off-by: Richard Zhao Signed-off-by: Sascha Hauer Signed-off-by: Shawn Guo Cc: David S. Miller Acked-by: Marek Vasut --- drivers/net/ethernet/freescale/fec.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/net/ethernet/freescale/fec.c b/drivers/net/ethernet/freescale/fec.c index c136230d50b..112af9b056d 100644 --- a/drivers/net/ethernet/freescale/fec.c +++ b/drivers/net/ethernet/freescale/fec.c @@ -1591,7 +1591,7 @@ fec_probe(struct platform_device *pdev) ret = PTR_ERR(fep->clk); goto failed_clk; } - clk_enable(fep->clk); + clk_prepare_enable(fep->clk); ret = fec_enet_init(ndev); if (ret) @@ -1614,7 +1614,7 @@ failed_register: fec_enet_mii_remove(fep); failed_mii_init: failed_init: - clk_disable(fep->clk); + clk_disable_unprepare(fep->clk); clk_put(fep->clk); failed_clk: for (i = 0; i < FEC_IRQ_NUM; i++) { @@ -1641,7 +1641,7 @@ fec_drv_remove(struct platform_device *pdev) fec_stop(ndev); fec_enet_mii_remove(fep); - clk_disable(fep->clk); + clk_disable_unprepare(fep->clk); clk_put(fep->clk); iounmap(fep->hwp); unregister_netdev(ndev); @@ -1667,7 +1667,7 @@ fec_suspend(struct device *dev) fec_stop(ndev); netif_device_detach(ndev); } - clk_disable(fep->clk); + clk_disable_unprepare(fep->clk); return 0; } @@ -1678,7 +1678,7 @@ fec_resume(struct device *dev) struct net_device *ndev = dev_get_drvdata(dev); struct fec_enet_private *fep = netdev_priv(ndev); - clk_enable(fep->clk); + clk_prepare_enable(fep->clk); if (netif_running(ndev)) { fec_restart(ndev, fep->full_duplex); netif_device_attach(ndev); From 759a2e30d288032130f1f77092e72d4ec87ad4d0 Mon Sep 17 00:00:00 2001 From: Shawn Guo Date: Tue, 20 Dec 2011 13:54:00 +0800 Subject: [PATCH 04/12] dma: mxs-dma: convert to clk_prepare/clk_unprepare The patch converts mxs-dma driver to clk_prepare/clk_unprepare by using helper functions clk_prepare_enable/clk_disable_unprepare. Signed-off-by: Shawn Guo Acked-by: Marek Vasut Acked-by: Vinod Koul --- drivers/dma/mxs-dma.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/dma/mxs-dma.c b/drivers/dma/mxs-dma.c index b4588bdd98b..fc903c0ed23 100644 --- a/drivers/dma/mxs-dma.c +++ b/drivers/dma/mxs-dma.c @@ -334,7 +334,7 @@ static int mxs_dma_alloc_chan_resources(struct dma_chan *chan) goto err_irq; } - ret = clk_enable(mxs_dma->clk); + ret = clk_prepare_enable(mxs_dma->clk); if (ret) goto err_clk; @@ -372,7 +372,7 @@ static void mxs_dma_free_chan_resources(struct dma_chan *chan) dma_free_coherent(mxs_dma->dma_device.dev, PAGE_SIZE, mxs_chan->ccw, mxs_chan->ccw_phys); - clk_disable(mxs_dma->clk); + clk_disable_unprepare(mxs_dma->clk); } static struct dma_async_tx_descriptor *mxs_dma_prep_slave_sg( @@ -578,7 +578,7 @@ static int __init mxs_dma_init(struct mxs_dma_engine *mxs_dma) { int ret; - ret = clk_enable(mxs_dma->clk); + ret = clk_prepare_enable(mxs_dma->clk); if (ret) goto err_out; @@ -604,7 +604,7 @@ static int __init mxs_dma_init(struct mxs_dma_engine *mxs_dma) writel(MXS_DMA_CHANNELS_MASK << MXS_DMA_CHANNELS, mxs_dma->base + HW_APBHX_CTRL1 + MXS_SET_ADDR); - clk_disable(mxs_dma->clk); + clk_disable_unprepare(mxs_dma->clk); return 0; From efdfc52c0470fb650cb2ee44cf030ec04e97b954 Mon Sep 17 00:00:00 2001 From: Shawn Guo Date: Tue, 20 Dec 2011 13:57:41 +0800 Subject: [PATCH 05/12] mmc: mxs-mmc: convert to clk_prepare/clk_unprepare The patch converts mxs-mmc driver to clk_prepare/clk_unprepare by using helper functions clk_prepare_enable/clk_disable_unprepare. Signed-off-by: Shawn Guo Cc: Chris Ball Acked-by: Marek Vasut --- drivers/mmc/host/mxs-mmc.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/mmc/host/mxs-mmc.c b/drivers/mmc/host/mxs-mmc.c index 99b449d26a4..973011f9a29 100644 --- a/drivers/mmc/host/mxs-mmc.c +++ b/drivers/mmc/host/mxs-mmc.c @@ -713,7 +713,7 @@ static int mxs_mmc_probe(struct platform_device *pdev) ret = PTR_ERR(host->clk); goto out_iounmap; } - clk_enable(host->clk); + clk_prepare_enable(host->clk); mxs_mmc_reset(host); @@ -772,7 +772,7 @@ out_free_dma: if (host->dmach) dma_release_channel(host->dmach); out_clk_put: - clk_disable(host->clk); + clk_disable_unprepare(host->clk); clk_put(host->clk); out_iounmap: iounmap(host->base); @@ -798,7 +798,7 @@ static int mxs_mmc_remove(struct platform_device *pdev) if (host->dmach) dma_release_channel(host->dmach); - clk_disable(host->clk); + clk_disable_unprepare(host->clk); clk_put(host->clk); iounmap(host->base); @@ -819,7 +819,7 @@ static int mxs_mmc_suspend(struct device *dev) ret = mmc_suspend_host(mmc); - clk_disable(host->clk); + clk_disable_unprepare(host->clk); return ret; } @@ -830,7 +830,7 @@ static int mxs_mmc_resume(struct device *dev) struct mxs_mmc_host *host = mmc_priv(mmc); int ret = 0; - clk_enable(host->clk); + clk_prepare_enable(host->clk); ret = mmc_resume_host(mmc); From f1f802c9026da6774a72963178ff7435f539fb09 Mon Sep 17 00:00:00 2001 From: Shawn Guo Date: Tue, 20 Dec 2011 14:02:05 +0800 Subject: [PATCH 06/12] mtd: gpmi-lib: convert to clk_prepare/clk_unprepare The patch converts gpmi nand driver to clk_prepare/clk_unprepare by using helper functions clk_prepare_enable/clk_disable_unprepare. Signed-off-by: Shawn Guo Cc: Huang Shijie Cc: Artem Bityutskiy Acked-by: Marek Vasut --- drivers/mtd/nand/gpmi-nand/gpmi-lib.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-lib.c b/drivers/mtd/nand/gpmi-nand/gpmi-lib.c index de4db7604a3..2a56fc6f399 100644 --- a/drivers/mtd/nand/gpmi-nand/gpmi-lib.c +++ b/drivers/mtd/nand/gpmi-nand/gpmi-lib.c @@ -126,7 +126,7 @@ int gpmi_init(struct gpmi_nand_data *this) struct resources *r = &this->resources; int ret; - ret = clk_enable(r->clock); + ret = clk_prepare_enable(r->clock); if (ret) goto err_out; ret = gpmi_reset_block(r->gpmi_regs, false); @@ -146,7 +146,7 @@ int gpmi_init(struct gpmi_nand_data *this) /* Select BCH ECC. */ writel(BM_GPMI_CTRL1_BCH_MODE, r->gpmi_regs + HW_GPMI_CTRL1_SET); - clk_disable(r->clock); + clk_disable_unprepare(r->clock); return 0; err_out: return ret; @@ -202,7 +202,7 @@ int bch_set_geometry(struct gpmi_nand_data *this) ecc_strength = bch_geo->ecc_strength >> 1; page_size = bch_geo->page_size; - ret = clk_enable(r->clock); + ret = clk_prepare_enable(r->clock); if (ret) goto err_out; @@ -229,7 +229,7 @@ int bch_set_geometry(struct gpmi_nand_data *this) writel(BM_BCH_CTRL_COMPLETE_IRQ_EN, r->bch_regs + HW_BCH_CTRL_SET); - clk_disable(r->clock); + clk_disable_unprepare(r->clock); return 0; err_out: return ret; @@ -704,7 +704,7 @@ void gpmi_begin(struct gpmi_nand_data *this) int ret; /* Enable the clock. */ - ret = clk_enable(r->clock); + ret = clk_prepare_enable(r->clock); if (ret) { pr_err("We failed in enable the clk\n"); goto err_out; @@ -773,7 +773,7 @@ err_out: void gpmi_end(struct gpmi_nand_data *this) { struct resources *r = &this->resources; - clk_disable(r->clock); + clk_disable_unprepare(r->clock); } /* Clears a BCH interrupt. */ From e735489976c356a189f7332e6ff4b0dee2ede434 Mon Sep 17 00:00:00 2001 From: Shawn Guo Date: Tue, 20 Dec 2011 14:05:52 +0800 Subject: [PATCH 07/12] net: flexcan: convert to clk_prepare/clk_unprepare The patch converts flexcan driver to clk_prepare/clk_unprepare by using helper functions clk_prepare_enable/clk_disable_unprepare. Signed-off-by: Shawn Guo Cc: Marc Kleine-Budde Cc: David S. Miller --- drivers/net/can/flexcan.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c index e02337953f4..fdd0f3fbeab 100644 --- a/drivers/net/can/flexcan.c +++ b/drivers/net/can/flexcan.c @@ -802,7 +802,7 @@ static int flexcan_open(struct net_device *dev) struct flexcan_priv *priv = netdev_priv(dev); int err; - clk_enable(priv->clk); + clk_prepare_enable(priv->clk); err = open_candev(dev); if (err) @@ -824,7 +824,7 @@ static int flexcan_open(struct net_device *dev) out_close: close_candev(dev); out: - clk_disable(priv->clk); + clk_disable_unprepare(priv->clk); return err; } @@ -838,7 +838,7 @@ static int flexcan_close(struct net_device *dev) flexcan_chip_stop(dev); free_irq(dev->irq, dev); - clk_disable(priv->clk); + clk_disable_unprepare(priv->clk); close_candev(dev); @@ -877,7 +877,7 @@ static int __devinit register_flexcandev(struct net_device *dev) struct flexcan_regs __iomem *regs = priv->base; u32 reg, err; - clk_enable(priv->clk); + clk_prepare_enable(priv->clk); /* select "bus clock", chip must be disabled */ flexcan_chip_disable(priv); @@ -911,7 +911,7 @@ static int __devinit register_flexcandev(struct net_device *dev) out: /* disable core and turn off clocks */ flexcan_chip_disable(priv); - clk_disable(priv->clk); + clk_disable_unprepare(priv->clk); return err; } From a481377013c1c07dac0421886db7a6b4c3081c49 Mon Sep 17 00:00:00 2001 From: Shawn Guo Date: Tue, 20 Dec 2011 14:10:29 +0800 Subject: [PATCH 08/12] serial: mxs-auart: convert to clk_prepare/clk_unprepare The patch converts mxs-auart driver to clk_prepare/clk_unprepare by using helper functions clk_prepare_enable/clk_disable_unprepare. Signed-off-by: Shawn Guo Cc: Sascha Hauer Cc: Alan Cox --- drivers/tty/serial/mxs-auart.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/tty/serial/mxs-auart.c b/drivers/tty/serial/mxs-auart.c index 7e02c9c344f..c33500a5e03 100644 --- a/drivers/tty/serial/mxs-auart.c +++ b/drivers/tty/serial/mxs-auart.c @@ -424,7 +424,7 @@ static int mxs_auart_startup(struct uart_port *u) { struct mxs_auart_port *s = to_auart_port(u); - clk_enable(s->clk); + clk_prepare_enable(s->clk); writel(AUART_CTRL0_CLKGATE, u->membase + AUART_CTRL0_CLR); @@ -453,7 +453,7 @@ static void mxs_auart_shutdown(struct uart_port *u) writel(AUART_INTR_RXIEN | AUART_INTR_RTIEN | AUART_INTR_CTSMIEN, u->membase + AUART_INTR_CLR); - clk_disable(s->clk); + clk_disable_unprepare(s->clk); } static unsigned int mxs_auart_tx_empty(struct uart_port *u) @@ -634,7 +634,7 @@ auart_console_setup(struct console *co, char *options) if (!s) return -ENODEV; - clk_enable(s->clk); + clk_prepare_enable(s->clk); if (options) uart_parse_options(options, &baud, &parity, &bits, &flow); @@ -643,7 +643,7 @@ auart_console_setup(struct console *co, char *options) ret = uart_set_options(&s->port, co, baud, parity, bits, flow); - clk_disable(s->clk); + clk_disable_unprepare(s->clk); return ret; } From ca4c22d391b8a5ac2b79135213ca68abc7aeb984 Mon Sep 17 00:00:00 2001 From: Shawn Guo Date: Tue, 20 Dec 2011 14:12:54 +0800 Subject: [PATCH 09/12] video: mxsfb: convert to clk_prepare/clk_unprepare The patch converts mxsfb driver to clk_prepare/clk_unprepare by using helper functions clk_prepare_enable/clk_disable_unprepare. Signed-off-by: Shawn Guo Cc: Sascha Hauer Acked-by: Marek Vasut Acked-by: Florian Tobias Schandinat --- drivers/video/mxsfb.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/video/mxsfb.c b/drivers/video/mxsfb.c index d837d63c456..eb3c5eea1a0 100644 --- a/drivers/video/mxsfb.c +++ b/drivers/video/mxsfb.c @@ -328,7 +328,7 @@ static void mxsfb_enable_controller(struct fb_info *fb_info) dev_dbg(&host->pdev->dev, "%s\n", __func__); - clk_enable(host->clk); + clk_prepare_enable(host->clk); clk_set_rate(host->clk, PICOS2KHZ(fb_info->var.pixclock) * 1000U); /* if it was disabled, re-enable the mode again */ @@ -368,7 +368,7 @@ static void mxsfb_disable_controller(struct fb_info *fb_info) writel(VDCTRL4_SYNC_SIGNALS_ON, host->base + LCDC_VDCTRL4 + REG_CLR); - clk_disable(host->clk); + clk_disable_unprepare(host->clk); host->enabled = 0; } @@ -668,7 +668,7 @@ static int __devinit mxsfb_restore_mode(struct mxsfb_info *host) line_count = fb_info->fix.smem_len / fb_info->fix.line_length; fb_info->fix.ypanstep = 1; - clk_enable(host->clk); + clk_prepare_enable(host->clk); host->enabled = 1; return 0; @@ -841,7 +841,7 @@ static int __devinit mxsfb_probe(struct platform_device *pdev) error_register: if (host->enabled) - clk_disable(host->clk); + clk_disable_unprepare(host->clk); fb_destroy_modelist(&fb_info->modelist); error_init_fb: kfree(fb_info->pseudo_palette); From 67939b22dadd6c5cbf7a4abe9eaec3a8415569a7 Mon Sep 17 00:00:00 2001 From: Shawn Guo Date: Tue, 20 Dec 2011 14:15:44 +0800 Subject: [PATCH 10/12] ASoC: mxs-saif: convert to clk_prepare/clk_unprepare The patch converts mxs-saif driver to clk_prepare/clk_unprepare by using helper functions clk_prepare_enable/clk_disable_unprepare. Signed-off-by: Shawn Guo Cc: Dong Aisheng Cc: Liam Girdwood Acked-by: Mark Brown Acked-by: Marek Vasut --- sound/soc/mxs/mxs-saif.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/sound/soc/mxs/mxs-saif.c b/sound/soc/mxs/mxs-saif.c index 76dc74d24fc..ef1abb53af9 100644 --- a/sound/soc/mxs/mxs-saif.c +++ b/sound/soc/mxs/mxs-saif.c @@ -210,7 +210,7 @@ int mxs_saif_put_mclk(unsigned int saif_id) return -EBUSY; } - clk_disable(saif->clk); + clk_disable_unprepare(saif->clk); /* disable MCLK output */ __raw_writel(BM_SAIF_CTRL_CLKGATE, @@ -264,7 +264,7 @@ int mxs_saif_get_mclk(unsigned int saif_id, unsigned int mclk, if (ret) return ret; - ret = clk_enable(saif->clk); + ret = clk_prepare_enable(saif->clk); if (ret) return ret; From 5c77f5608a5081632b9530e5f3260f8b63247bd8 Mon Sep 17 00:00:00 2001 From: Shawn Guo Date: Tue, 20 Dec 2011 14:46:38 +0800 Subject: [PATCH 11/12] clk: add config option HAVE_CLK_PREPARE into Kconfig The commit 40d3e0f (clk: provide prepare/unprepare functions) provides the config option HAVE_CLK_PREPARE for platforms that have prepare/unprepare implementation to select. This patch adds the option into drivers/clk/Kconfig, so that it can be actually selected. Signed-off-by: Shawn Guo Cc: Russell King --- drivers/clk/Kconfig | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig index 35309274ad6..9b3cd08cd0e 100644 --- a/drivers/clk/Kconfig +++ b/drivers/clk/Kconfig @@ -3,5 +3,8 @@ config CLKDEV_LOOKUP bool select HAVE_CLK +config HAVE_CLK_PREPARE + bool + config HAVE_MACH_CLKDEV bool From 6abda3e129bfe4d74b5c274da7dff0e2b1488818 Mon Sep 17 00:00:00 2001 From: Shawn Guo Date: Tue, 20 Dec 2011 16:12:34 +0800 Subject: [PATCH 12/12] ARM: mxs: select HAVE_CLK_PREPARE for clock This patch adds clk_prepare/clk_unprepare for mxs clock api by renaming the existing non-atomic clk_enable/clk_disable to clk_prepare/clk_unprepare and adding a pair of dummy clk_enable/clk_disable. Then with selecting HAVE_CLK_PREPARE for mxs clock, we can fix the mutex locking warning that has been reported for a few times. Signed-off-by: Shawn Guo --- arch/arm/Kconfig | 1 + arch/arm/mach-mxs/clock.c | 31 ++++++++++++++++++++++--------- 2 files changed, 23 insertions(+), 9 deletions(-) diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 776d76b8cb6..dc461637e77 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -442,6 +442,7 @@ config ARCH_MXS select ARCH_REQUIRE_GPIOLIB select CLKDEV_LOOKUP select CLKSRC_MMIO + select HAVE_CLK_PREPARE help Support for Freescale MXS-based family of processors diff --git a/arch/arm/mach-mxs/clock.c b/arch/arm/mach-mxs/clock.c index 755eec0b5a8..97a6f4acc6c 100644 --- a/arch/arm/mach-mxs/clock.c +++ b/arch/arm/mach-mxs/clock.c @@ -74,10 +74,15 @@ static int __clk_enable(struct clk *clk) return 0; } -/* This function increments the reference count on the clock and enables the - * clock if not already enabled. The parent clock tree is recursively enabled +/* + * The clk_enable/clk_disable could be called by drivers in atomic context, + * so they should not really hold mutex. Instead, clk_prepare/clk_unprepare + * can hold a mutex, as the pair will only be called in non-atomic context. + * Before migrating to common clk framework, we can have __clk_enable and + * __clk_disable called in clk_prepare/clk_unprepare with mutex held and + * leave clk_enable/clk_disable as the dummy functions. */ -int clk_enable(struct clk *clk) +int clk_prepare(struct clk *clk) { int ret = 0; @@ -90,13 +95,9 @@ int clk_enable(struct clk *clk) return ret; } -EXPORT_SYMBOL(clk_enable); +EXPORT_SYMBOL(clk_prepare); -/* This function decrements the reference count on the clock and disables - * the clock when reference count is 0. The parent clock tree is - * recursively disabled - */ -void clk_disable(struct clk *clk) +void clk_unprepare(struct clk *clk) { if (clk == NULL || IS_ERR(clk)) return; @@ -105,6 +106,18 @@ void clk_disable(struct clk *clk) __clk_disable(clk); mutex_unlock(&clocks_mutex); } +EXPORT_SYMBOL(clk_unprepare); + +int clk_enable(struct clk *clk) +{ + return 0; +} +EXPORT_SYMBOL(clk_enable); + +void clk_disable(struct clk *clk) +{ + /* nothing to do */ +} EXPORT_SYMBOL(clk_disable); /* Retrieve the *current* clock rate. If the clock itself