From f7cccb2e66f0187f69a432536f227b32a458f94b Mon Sep 17 00:00:00 2001 From: Martin Sperl Date: Tue, 26 Apr 2016 14:59:21 +0000 Subject: [PATCH] MISC: bcm2835: smi: use clock manager and fix reload issues Use clock manager instead of self-made clockmanager. Also fix some error paths that showd up during development (especially missing release of dma resources on rmmod) Signed-off-by: Martin Sperl --- drivers/misc/bcm2835_smi.c | 86 +++++++++++++------------------------- 1 file changed, 28 insertions(+), 58 deletions(-) --- a/drivers/misc/bcm2835_smi.c +++ b/drivers/misc/bcm2835_smi.c @@ -34,6 +34,7 @@ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ +#include #include #include #include @@ -62,7 +63,7 @@ struct bcm2835_smi_instance { struct device *dev; struct smi_settings settings; - __iomem void *smi_regs_ptr, *cm_smi_regs_ptr; + __iomem void *smi_regs_ptr; dma_addr_t smi_regs_busaddr; struct dma_chan *dma_chan; @@ -72,8 +73,7 @@ struct bcm2835_smi_instance { struct scatterlist buffer_sgl; - int clock_source; - int clock_divisor; + struct clk *clk; /* Sometimes we are called into in an atomic context (e.g. by JFFS2 + MTD) so we can't use a mutex */ @@ -82,42 +82,6 @@ struct bcm2835_smi_instance { /**************************************************************************** * -* SMI clock manager setup -* -***************************************************************************/ - -static inline void write_smi_cm_reg(struct bcm2835_smi_instance *inst, - u32 val, unsigned reg) -{ - writel(CM_PWD | val, inst->cm_smi_regs_ptr + reg); -} - -static inline u32 read_smi_cm_reg(struct bcm2835_smi_instance *inst, - unsigned reg) -{ - return readl(inst->cm_smi_regs_ptr + reg); -} - -static void smi_setup_clock(struct bcm2835_smi_instance *inst) -{ - dev_dbg(inst->dev, "Setting up clock..."); - /* Disable SMI clock and wait for it to stop. */ - write_smi_cm_reg(inst, 0, CM_SMI_CTL); - while (read_smi_cm_reg(inst, CM_SMI_CTL) & CM_SMI_CTL_BUSY) - ; - - write_smi_cm_reg(inst, (inst->clock_divisor << CM_SMI_DIV_DIVI_OFFS), - CM_SMI_DIV); - write_smi_cm_reg(inst, (inst->clock_source << CM_SMI_CTL_SRC_OFFS), - CM_SMI_CTL); - - /* Enable the clock */ - write_smi_cm_reg(inst, (inst->clock_source << CM_SMI_CTL_SRC_OFFS) | - CM_SMI_CTL_ENAB, CM_SMI_CTL); -} - -/**************************************************************************** -* * SMI peripheral setup * ***************************************************************************/ @@ -894,42 +858,40 @@ static int bcm2835_smi_probe(struct plat struct device_node *node = dev->of_node; struct resource *ioresource; struct bcm2835_smi_instance *inst; + const __be32 *addr; + /* We require device tree support */ + if (!node) + return -EINVAL; /* Allocate buffers and instance data */ - inst = devm_kzalloc(dev, sizeof(struct bcm2835_smi_instance), GFP_KERNEL); - if (!inst) return -ENOMEM; inst->dev = dev; spin_lock_init(&inst->transaction_lock); - /* We require device tree support */ - if (!node) - return -EINVAL; - ioresource = platform_get_resource(pdev, IORESOURCE_MEM, 0); inst->smi_regs_ptr = devm_ioremap_resource(dev, ioresource); - ioresource = platform_get_resource(pdev, IORESOURCE_MEM, 1); - inst->cm_smi_regs_ptr = devm_ioremap_resource(dev, ioresource); - inst->smi_regs_busaddr = be32_to_cpu( - *of_get_address(node, 0, NULL, NULL)); - of_property_read_u32(node, - "brcm,smi-clock-source", - &inst->clock_source); - of_property_read_u32(node, - "brcm,smi-clock-divisor", - &inst->clock_divisor); + if (IS_ERR(inst->smi_regs_ptr)) { + err = PTR_ERR(inst->smi_regs_ptr); + goto err; + } + addr = of_get_address(node, 0, NULL, NULL); + inst->smi_regs_busaddr = be32_to_cpu(addr); err = bcm2835_smi_dma_setup(inst); if (err) - return err; + goto err; - /* Finally, do peripheral setup */ + /* request clock */ + inst->clk = devm_clk_get(dev, NULL); + if (!inst->clk) + goto err; + clk_prepare_enable(inst->clk); - smi_setup_clock(inst); + /* Finally, do peripheral setup */ smi_setup_regs(inst); platform_set_drvdata(pdev, inst); @@ -937,6 +899,9 @@ static int bcm2835_smi_probe(struct plat dev_info(inst->dev, "initialised"); return 0; +err: + kfree(inst); + return err; } /**************************************************************************** @@ -950,6 +915,11 @@ static int bcm2835_smi_remove(struct pla struct bcm2835_smi_instance *inst = platform_get_drvdata(pdev); struct device *dev = inst->dev; + dmaengine_terminate_all(inst->dma_chan); + dma_release_channel(inst->dma_chan); + + clk_disable_unprepare(inst->clk); + dev_info(dev, "SMI device removed - OK"); return 0; }