Use of provided plat_read/plat_write introduces the problem of possible different lifetime of rtc driver and plat_XXX function provider. As this was only intended for SGI Octane (IP30) this patchset implements a register indirect access method for IP30 and introduces an access_type field in platform data to select how registers are accessed. And since there are no resource allocating stunts needed anymore it also gets rid of alloc_io_resources from platform data.
Signed-off-by: Thomas Bogendoerfer <[email protected]> --- arch/mips/sgi-ip32/ip32-platform.c | 2 +- drivers/rtc/rtc-ds1685.c | 67 ++++++++++++++++++++++++-------------- include/linux/rtc/ds1685.h | 8 +++-- 3 files changed, 48 insertions(+), 29 deletions(-) diff --git a/arch/mips/sgi-ip32/ip32-platform.c b/arch/mips/sgi-ip32/ip32-platform.c index 5a2a82148d8d..c3909bd8dd1a 100644 --- a/arch/mips/sgi-ip32/ip32-platform.c +++ b/arch/mips/sgi-ip32/ip32-platform.c @@ -115,7 +115,7 @@ ip32_rtc_platform_data[] = { .bcd_mode = true, .no_irq = false, .uie_unsupported = false, - .alloc_io_resources = true, + .access_type = ds1685_reg_direct, .plat_prepare_poweroff = ip32_prepare_poweroff, }, }; diff --git a/drivers/rtc/rtc-ds1685.c b/drivers/rtc/rtc-ds1685.c index 349a8d1caca1..9c5d064ebb6c 100644 --- a/drivers/rtc/rtc-ds1685.c +++ b/drivers/rtc/rtc-ds1685.c @@ -59,6 +59,32 @@ ds1685_write(struct ds1685_priv *rtc, int reg, u8 value) } /* ----------------------------------------------------------------------- */ +/* Indirect read/write functions */ + +/** + * ds1685_indir_read - read a value from an rtc register. + * @rtc: pointer to the ds1685 rtc structure. + * @reg: the register address to read. + */ +static u8 +ds1685_indir_read(struct ds1685_priv *rtc, int reg) +{ + writeb(reg, rtc->regs); + return readb(rtc->data); +} + +/** + * ds1685_indir_write - write a value to an rtc register. + * @rtc: pointer to the ds1685 rtc structure. + * @reg: the register address to write. + * @value: value to write to the register. + */ +static void +ds1685_indir_write(struct ds1685_priv *rtc, int reg, u8 value) +{ + writeb(reg, rtc->regs); + writeb(value, rtc->data); +} /* ----------------------------------------------------------------------- */ /* Inlined functions */ @@ -1062,16 +1088,25 @@ ds1685_rtc_probe(struct platform_device *pdev) if (!rtc) return -ENOMEM; - /* - * Allocate/setup any IORESOURCE_MEM resources, if required. Not all - * platforms put the RTC in an easy-access place. Like the SGI Octane, - * which attaches the RTC to a "ByteBus", hooked to a SuperIO chip - * that sits behind the IOC3 PCI metadevice. - */ - if (pdata->alloc_io_resources) { + /* Setup resources and access functions */ + switch (pdata->access_type) { + case ds1685_reg_direct: + rtc->regs = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(rtc->regs)) + return PTR_ERR(rtc->regs); + rtc->read = ds1685_read; + rtc->write = ds1685_write; + break; + case ds1685_reg_indirect: rtc->regs = devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(rtc->regs)) return PTR_ERR(rtc->regs); + rtc->data = devm_platform_ioremap_resource(pdev, 1); + if (IS_ERR(rtc->data)) + return PTR_ERR(rtc->data); + rtc->read = ds1685_indir_read; + rtc->write = ds1685_indir_write; + break; } /* Get the register step size. */ @@ -1080,24 +1115,6 @@ ds1685_rtc_probe(struct platform_device *pdev) else rtc->regstep = 1; - /* Platform read function, else default if mmio setup */ - if (pdata->plat_read) - rtc->read = pdata->plat_read; - else - if (pdata->alloc_io_resources) - rtc->read = ds1685_read; - else - return -ENXIO; - - /* Platform write function, else default if mmio setup */ - if (pdata->plat_write) - rtc->write = pdata->plat_write; - else - if (pdata->alloc_io_resources) - rtc->write = ds1685_write; - else - return -ENXIO; - /* Platform pre-shutdown function, if defined. */ if (pdata->plat_prepare_poweroff) rtc->prepare_poweroff = pdata->plat_prepare_poweroff; diff --git a/include/linux/rtc/ds1685.h b/include/linux/rtc/ds1685.h index 101c7adc05a2..67ee9d20cc5a 100644 --- a/include/linux/rtc/ds1685.h +++ b/include/linux/rtc/ds1685.h @@ -42,6 +42,7 @@ struct ds1685_priv { struct rtc_device *dev; void __iomem *regs; + void __iomem *data; u32 regstep; int irq_num; bool bcd_mode; @@ -70,12 +71,13 @@ struct ds1685_rtc_platform_data { const bool bcd_mode; const bool no_irq; const bool uie_unsupported; - const bool alloc_io_resources; - u8 (*plat_read)(struct ds1685_priv *, int); - void (*plat_write)(struct ds1685_priv *, int, u8); void (*plat_prepare_poweroff)(void); void (*plat_wake_alarm)(void); void (*plat_post_ram_clear)(void); + enum { + ds1685_reg_direct, + ds1685_reg_indirect + } access_type; }; -- 2.16.4
