Ben Dooks wrote: > > On Thu, Jun 10, 2010 at 04:50:41PM +0900, Kukjin Kim wrote: > > From: Abhilash Kesavan <a.kesavan@xxxxxxxxxxx> > > > > Adds support for the Samsung PATA controller. This driver is based on the > > Libata subsystem and references the earlier patches sent for IDE subsystem. > > Thanks for your review. :-) > > Signed-off-by: Abhilash Kesavan <a.kesavan@xxxxxxxxxxx> > > Signed-off-by: Kukjin Kim <kgene.kim@xxxxxxxxxxx> > > a few more comments, you may or may not want to fix before first > submission. > > > --- > > > > Changes since v2: > > - Changed the DRV_NAME to pata_samsung_cf > > - Used msleep instead of mdelay > > > > drivers/ata/Makefile | 1 + > > drivers/ata/pata_samsung_cf.c | 608 > +++++++++++++++++++++++++++++++++++++++++ > > 3 files changed, 618 insertions(+), 0 deletions(-) > > create mode 100644 drivers/ata/pata_samsung_cf.c > > > > diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig > > index aa85a98..1b5facf 100644 > > --- a/drivers/ata/Kconfig > > +++ b/drivers/ata/Kconfig > > @@ -796,6 +796,15 @@ config PATA_RZ1000 > > > > If unsure, say N. > > > > +config PATA_SAMSUNG_CF > > + tristate "Samsung SoC PATA support" > > + depends on SAMSUNG_DEV_IDE > > + help > > + This option enables basic support for Samsung's S3C/S5P board > > + PATA controllers via the new ATA layer > > + > > + If unsure, say N. > > + > > config PATA_WINBOND_VLB > > tristate "Winbond W83759A VLB PATA support (Experimental)" > > depends on ISA && EXPERIMENTAL > > diff --git a/drivers/ata/Makefile b/drivers/ata/Makefile > > index 7ef89d7..9576776 100644 > > --- a/drivers/ata/Makefile > > +++ b/drivers/ata/Makefile > > @@ -87,6 +87,7 @@ obj-$(CONFIG_PATA_OF_PLATFORM) += > pata_of_platform.o > > obj-$(CONFIG_PATA_QDI) += pata_qdi.o > > obj-$(CONFIG_PATA_RB532) += pata_rb532_cf.o > > obj-$(CONFIG_PATA_RZ1000) += pata_rz1000.o > > +obj-$(CONFIG_PATA_SAMSUNG_CF) += pata_samsung_cf.o > > obj-$(CONFIG_PATA_WINBOND_VLB) += pata_winbond.o > > > > # Should be last but two libata driver > > diff --git a/drivers/ata/pata_samsung_cf.c b/drivers/ata/pata_samsung_cf.c > > new file mode 100644 > > index 0000000..fef5515 > > --- /dev/null > > +++ b/drivers/ata/pata_samsung_cf.c > > @@ -0,0 +1,608 @@ > > +/* linux/drivers/ata/pata_samsung_cf.c > > + * > > + * Copyright (c) 2010 Samsung Electronics Co., Ltd. > > + * http://www.samsung.com > > + * > > + * PATA driver for Samsung SoCs. > > + * Supports CF Interface in True IDE mode. Currently only PIO mode has been > > + * implemented; UDMA support has to be added. > > + * > > + * Based on: > > + * PATA driver for AT91SAM9260 Static Memory Controller > > + * PATA driver for Toshiba SCC controller > > + * > > + * This program is free software; you can redistribute it and/or modify it > > + * under the terms of the GNU General Public License version 2 > > + * as published by the Free Software Foundation. > > +*/ > > + > > +#include <linux/kernel.h> > > +#include <linux/module.h> > > +#include <linux/init.h> > > +#include <linux/clk.h> > > +#include <linux/libata.h> > > +#include <linux/platform_device.h> > > +#include <linux/slab.h> > > + > > +#include <plat/ata.h> > > +#include <plat/regs-ata.h> > > + > > +#define DRV_NAME "pata_samsung_cf" > > +#define DRV_VERSION "0.1" > > + > > +enum s3c_cpu_type { > > + TYPE_S3C64XX, > > + TYPE_S5PC100, > > + TYPE_S5PV210, > > +}; > > + > > +/* > > + * struct s3c_ide_info - S3C PATA instance. > > + * @clk: The clock resource for this controller. > > + * @ide_addr: The area mapped for the hardware registers. > > + * @sfr_addr: The area mapped for the special function registers. > > + * @irq: The IRQ number we are using. > > + * @cpu_type: The exact type of this controller. > > + * @fifo_status_reg: The ATA_FIFO_STATUS register offset. > > + */ > > +struct s3c_ide_info { > > + struct clk *clk; > > + void __iomem *ide_addr; > > + void __iomem *sfr_addr; > > + unsigned int irq; > > + enum s3c_cpu_type cpu_type; > > + unsigned int fifo_status_reg; > > +}; > > + > > +static void pata_s3c_set_endian(void *s3c_ide_regbase, u8 mode) > > +{ > should be void __iomem. > OK. > > +static void pata_s3c_set_piomode(struct ata_port *ap, struct ata_device *adev) > > +{ > > + int mode = adev->pio_mode - XFER_PIO_0; > > + struct s3c_ide_info *info = ap->host->private_data; > > + ulong ata_cfg = readl(info->ide_addr + S3C_ATA_CFG); > > + ulong piotime; > > + > > + /* Calculates timing parameters for PIO mode */ > > + piotime = pata_s3c_setup_timing(info, adev); > > + > > + /* Enables IORDY if mode requires it */ > > + if (ata_pio_need_iordy(adev)) > > + ata_cfg |= S3C_ATA_CFG_IORDYEN; > > + else > > + ata_cfg &= ~S3C_ATA_CFG_IORDYEN; > > + > > + /* Host controller supports upto PIO4 only */ > > + if (mode >= 0 && mode <= 4) { > > if this code was to stay in, it would have been better to either > WARN_ON() or print some form of error messagee instead of just silently > ignoring it... also, you should have probably set the minumum acceptable > ATA mode to ensure any further actions would not cause problems with > trying to run the b us too fast. > Will remove the code..will set up the timing parameters using ata_timing_compute and the initial timing will be for PIO0 in case of failure. > > +/* > > + * Waits until the IDE controller is able to perform next read/write > > + * operation to the disk. Needed for 64XX series boards only. > > + */ > > if it is needed only for s3c64xx series, why don't we bail if the > info->type != 64xx? > This is called via pata_s3c_port_ops for 64xx else goes to pata_s5p_port_ops. > > +static int wait_for_host_ready(struct s3c_ide_info *info) > > +{ > > + ulong timeout; > > + > > + /* wait for maximum of 20 msec */ > > + timeout = jiffies + msecs_to_jiffies(20); > > + while (time_before(jiffies, timeout)) { > > + if ((readl(info->ide_addr + info->fifo_status_reg) >> 28) == 0) > > would be neater to have > void __iomem *fifo_reg = info->ide_addr + info->fifo_status_reg > ... > > while(...) { > if (readl(fifo_reg) >> 28) == 0) > ... > OK. > > + return 0; > > + } > > + return -EBUSY; > > +} > > [snip] > > > +/* > > + * pata_s3c_data_xfer - Transfer data by PIO > > + */ > > +unsigned int pata_s3c_data_xfer(struct ata_device *dev, unsigned char *buf, > > + unsigned int buflen, int rw) > > +{ > > + struct ata_port *ap = dev->link->ap; > > + struct s3c_ide_info *info = ap->host->private_data; > > + void __iomem *data_addr = ap->ioaddr.data_addr; > > + unsigned int words = buflen >> 1, i; > > + u16 *data_ptr = (u16 *)buf; > > note, is there any chance of being passed a number of bytes? if so > should we at least WARN_ON(buflen & 1) and return an error? > Will add a WARN_ON. > > + if (rw == READ) > > + for (i = 0; i < words; i++, data_ptr++) { > > + wait_for_host_ready(info); > > + *data_ptr = readw(data_addr); > > + wait_for_host_ready(info); > > + *data_ptr = readw(info->ide_addr > > + + S3C_ATA_PIO_RDATA); > > + } Will add a description for read/write accesses. > > + else > > + for (i = 0; i < words; i++, data_ptr++) { > > + wait_for_host_ready(info); > > + writel(*data_ptr, data_addr); > > + } > > + > > + return words << 1; > > +} > > + > > +/* > > + * pata_s3c_dev_select - Select device on ATA bus > > + */ > > +static void pata_s3c_dev_select(struct ata_port *ap, unsigned int device) > > +{ > > + u8 tmp; > > + > > + if (device == 0) > > + tmp = ATA_DEVICE_OBS; > > + else > > + tmp = ATA_DEVICE_OBS | ATA_DEV1; > > you could have done > u8 tmp = ATA_DEVICE_OBS; > > if (device != 0) > tmp |= ATA_DEV1 > > > + ata_outb(ap->host, tmp, ap->ioaddr.device_addr); > > + ata_sff_pause(ap); > > +} > > + > > [snip] > > > +static void pata_s3c_enable(void *s3c_ide_regbase, u8 state) > state would be better as a bool or a natural int. OK. > > +{ > > + u32 temp = readl(s3c_ide_regbase + S3C_ATA_CTRL); > > + temp = state ? (temp | 1) : (temp & ~1); > > + writel(temp, s3c_ide_regbase + S3C_ATA_CTRL); > > +} > > + > > +static irqreturn_t pata_s3c_irq(int irq, void *dev_instance) > > +{ > > + struct ata_host *host = dev_instance; > > + struct s3c_ide_info *info = host->private_data; > > + u32 reg; > > + > > + reg = readl(info->ide_addr + S3C_ATA_IRQ); > > + writel(reg, info->ide_addr + S3C_ATA_IRQ); > > no decoding of the interrupt cause? > Others interrupts are for udma, mdma and EBI (we are using direct mode) and so I let them be. > > + return ata_sff_interrupt(irq, dev_instance); > > +} > > > +static int __devexit pata_s3c_remove(struct platform_device *pdev) > > +{ > > + struct ata_host *host = platform_get_drvdata(pdev); > > + struct s3c_ide_info *info; > > + struct resource *res; > > > + > > + if (!host) > > + return 0; > > don't think this check is really necessary. > OK. > > + info = host->private_data; > > + > > + ata_host_detach(host); > > + > > + clk_disable(info->clk); > > + clk_put(info->clk); > > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > > + release_mem_region(res->start, resource_size(res)); > > + kfree(info); > > + > > + return 0; > > +} > > + > > +#ifdef CONFIG_PM > > +static int pata_s3c_suspend(struct device *dev) > > +{ > > + struct platform_device *pdev = to_platform_device(dev); > > + struct ata_host *host = platform_get_drvdata(pdev); > > + pm_message_t state = PMSG_SUSPEND; > > + > > + if (host) > > + return ata_host_suspend(host, state); > > again, don't think you'l lget called here if you didn't sucessfully bind. > OK. > > + else > > + return 0; > > +} > > + > > +static int pata_s3c_resume(struct device *dev) > > +{ > > + struct platform_device *pdev = to_platform_device(dev); > > + struct ata_host *host = platform_get_drvdata(pdev); > > + struct s3c_ide_platdata *pdata = pdev->dev.platform_data; > > + struct s3c_ide_info *info; > > + > > + info = host->private_data; > > + > > + if (host) { > > + pata_s3c_hwinit(info, pdata); > > + ata_host_resume(host); > > + } > > + > > + return 0; > > +} > > + > > +static const struct dev_pm_ops pata_s3c_pm_ops = { > > + .suspend = pata_s3c_suspend, > > + .resume = pata_s3c_resume, > > +}; > > -- Thanks. Best regards, Kgene. -- Kukjin Kim <kgene.kim@xxxxxxxxxxx>, Senior Engineer, SW Solution Development Team, Samsung Electronics Co., Ltd. -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
 |