X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=arch%2Farm%2Fmach-pxa%2Fssp.c;h=6cc202755fb46c6ded53a8fe16512687ceb57f49;hb=97bf2856c6014879bd04983a3e9dfcdac1e7fe85;hp=50132a7c640c020d5b9cd39e85f98a05db5bbe2f;hpb=87fc8d1bb10cd459024a742c6a10961fefcef18f;p=linux-2.6.git diff --git a/arch/arm/mach-pxa/ssp.c b/arch/arm/mach-pxa/ssp.c index 50132a7c6..6cc202755 100644 --- a/arch/arm/mach-pxa/ssp.c +++ b/arch/arm/mach-pxa/ssp.c @@ -17,7 +17,10 @@ * * Revision history: * 22nd Aug 2003 Initial version. - * + * 20th Dec 2004 Added ssp_config for changing port config without + * closing the port. + * 4th Aug 2005 Added option to disable irq handler registration and + * cleaned up irq and clock detection. */ #include @@ -28,13 +31,41 @@ #include #include #include +#include #include #include #include #include #include -static irqreturn_t ssp_interrupt(int irq, void *dev_id, struct pt_regs *regs) +#define PXA_SSP_PORTS 3 + +#define TIMEOUT 100000 + +struct ssp_info_ { + int irq; + u32 clock; +}; + +/* + * SSP port clock and IRQ settings + */ +static const struct ssp_info_ ssp_info[PXA_SSP_PORTS] = { +#if defined (CONFIG_PXA27x) + {IRQ_SSP, CKEN23_SSP1}, + {IRQ_SSP2, CKEN3_SSP2}, + {IRQ_SSP3, CKEN4_SSP3}, +#else + {IRQ_SSP, CKEN3_SSP}, + {IRQ_NSSP, CKEN9_NSSP}, + {IRQ_ASSP, CKEN10_ASSP}, +#endif +}; + +static DEFINE_MUTEX(mutex); +static int use_count[PXA_SSP_PORTS] = {0, 0, 0}; + +static irqreturn_t ssp_interrupt(int irq, void *dev_id) { struct ssp_dev *dev = (struct ssp_dev*) dev_id; unsigned int status = SSSR_P(dev->port); @@ -63,13 +94,18 @@ static irqreturn_t ssp_interrupt(int irq, void *dev_id, struct pt_regs *regs) * The caller is expected to perform the necessary locking. * * Returns: - * %-ETIMEDOUT timeout occurred (for future) + * %-ETIMEDOUT timeout occurred * 0 success */ int ssp_write_word(struct ssp_dev *dev, u32 data) { - while (!(SSSR_P(dev->port) & SSSR_TNF)) + int timeout = TIMEOUT; + + while (!(SSSR_P(dev->port) & SSSR_TNF)) { + if (!--timeout) + return -ETIMEDOUT; cpu_relax(); + } SSDR_P(dev->port) = data; @@ -88,15 +124,21 @@ int ssp_write_word(struct ssp_dev *dev, u32 data) * The caller is expected to perform the necessary locking. * * Returns: - * %-ETIMEDOUT timeout occurred (for future) + * %-ETIMEDOUT timeout occurred * 32-bit data success */ -int ssp_read_word(struct ssp_dev *dev) +int ssp_read_word(struct ssp_dev *dev, u32 *data) { - while (!(SSSR_P(dev->port) & SSSR_RNE)) + int timeout = TIMEOUT; + + while (!(SSSR_P(dev->port) & SSSR_RNE)) { + if (!--timeout) + return -ETIMEDOUT; cpu_relax(); + } - return SSDR_P(dev->port); + *data = SSDR_P(dev->port); + return 0; } /** @@ -107,13 +149,21 @@ int ssp_read_word(struct ssp_dev *dev) * * The caller is expected to perform the necessary locking. */ -void ssp_flush(struct ssp_dev *dev) +int ssp_flush(struct ssp_dev *dev) { + int timeout = TIMEOUT * 2; + do { while (SSSR_P(dev->port) & SSSR_RNE) { + if (!--timeout) + return -ETIMEDOUT; (void) SSDR_P(dev->port); } + if (!--timeout) + return -ETIMEDOUT; } while (SSSR_P(dev->port) & SSSR_BSY); + + return 0; } /** @@ -170,6 +220,30 @@ void ssp_restore_state(struct ssp_dev *dev, struct ssp_state *ssp) SSCR0_P(dev->port) = ssp->cr0; } +/** + * ssp_config - configure SSP port settings + * @mode: port operating mode + * @flags: port config flags + * @psp_flags: port PSP config flags + * @speed: port speed + * + * Port MUST be disabled by ssp_disable before making any config changes. + */ +int ssp_config(struct ssp_dev *dev, u32 mode, u32 flags, u32 psp_flags, u32 speed) +{ + dev->mode = mode; + dev->flags = flags; + dev->psp_flags = psp_flags; + dev->speed = speed; + + /* set up port type, speed, port settings */ + SSCR0_P(dev->port) = (dev->speed | dev->mode); + SSCR1_P(dev->port) = dev->flags; + SSPSP_P(dev->port) = dev->psp_flags; + + return 0; +} + /** * ssp_init - setup the SSP port * @@ -180,82 +254,46 @@ void ssp_restore_state(struct ssp_dev *dev, struct ssp_state *ssp) * %-EBUSY if the resources are already in use * %0 on success */ -int ssp_init(struct ssp_dev *dev, u32 port, u32 mode, u32 flags, u32 psp_flags, - u32 speed) +int ssp_init(struct ssp_dev *dev, u32 port, u32 init_flags) { - int ret, irq; + int ret; - if (!request_mem_region(__PREG(SSCR0_P(port)), 0x2c, "SSP")) { + if (port > PXA_SSP_PORTS || port == 0) + return -ENODEV; + + mutex_lock(&mutex); + if (use_count[port - 1]) { + mutex_unlock(&mutex); return -EBUSY; } + use_count[port - 1]++; - switch (port) { - case 1: - irq = IRQ_SSP; - break; -#if defined (CONFIG_PXA27x) - case 2: - irq = IRQ_SSP2; - break; - case 3: - irq = IRQ_SSP3; - break; -#else - case 2: - irq = IRQ_NSSP; - break; - case 3: - irq = IRQ_ASSP; - break; -#endif - default: - return -ENODEV; + if (!request_mem_region(__PREG(SSCR0_P(port)), 0x2c, "SSP")) { + use_count[port - 1]--; + mutex_unlock(&mutex); + return -EBUSY; } - dev->port = port; - dev->mode = mode; - dev->flags = flags; - dev->psp_flags = psp_flags; - dev->speed = speed; - /* set up port type, speed, port settings */ - SSCR0_P(dev->port) = (dev->speed | dev->mode); - SSCR1_P(dev->port) = dev->flags; - SSPSP_P(dev->port) = dev->psp_flags; - - ret = request_irq(irq, ssp_interrupt, 0, "SSP", dev); - if (ret) - goto out_region; + /* do we need to get irq */ + if (!(init_flags & SSP_NO_IRQ)) { + ret = request_irq(ssp_info[port-1].irq, ssp_interrupt, + 0, "SSP", dev); + if (ret) + goto out_region; + dev->irq = ssp_info[port-1].irq; + } else + dev->irq = 0; /* turn on SSP port clock */ - switch (dev->port) { -#if defined (CONFIG_PXA27x) - case 1: - pxa_set_cken(CKEN23_SSP1, 1); - break; - case 2: - pxa_set_cken(CKEN3_SSP2, 1); - break; - case 3: - pxa_set_cken(CKEN4_SSP3, 1); - break; -#else - case 1: - pxa_set_cken(CKEN3_SSP, 1); - break; - case 2: - pxa_set_cken(CKEN9_NSSP, 1); - break; - case 3: - pxa_set_cken(CKEN10_ASSP, 1); - break; -#endif - } - + pxa_set_cken(ssp_info[port-1].clock, 1); + mutex_unlock(&mutex); return 0; out_region: - release_mem_region(__PREG(SSCR0_P(dev->port)), 0x2c); + release_mem_region(__PREG(SSCR0_P(port)), 0x2c); + use_count[port - 1]--; + mutex_unlock(&mutex); return ret; } @@ -266,46 +304,20 @@ out_region: */ void ssp_exit(struct ssp_dev *dev) { - int irq; - + mutex_lock(&mutex); SSCR0_P(dev->port) &= ~SSCR0_SSE; - /* find irq, save power and turn off SSP port clock */ - switch (dev->port) { -#if defined (CONFIG_PXA27x) - case 1: - irq = IRQ_SSP; - pxa_set_cken(CKEN23_SSP1, 0); - break; - case 2: - irq = IRQ_SSP2; - pxa_set_cken(CKEN3_SSP2, 0); - break; - case 3: - irq = IRQ_SSP3; - pxa_set_cken(CKEN4_SSP3, 0); - break; -#else - case 1: - irq = IRQ_SSP; - pxa_set_cken(CKEN3_SSP, 0); - break; - case 2: - irq = IRQ_NSSP; - pxa_set_cken(CKEN9_NSSP, 0); - break; - case 3: - irq = IRQ_ASSP; - pxa_set_cken(CKEN10_ASSP, 0); - break; -#endif - default: - printk(KERN_WARNING "SSP: tried to close invalid port\n"); - return; + if (dev->port > PXA_SSP_PORTS || dev->port == 0) { + printk(KERN_WARNING "SSP: tried to close invalid port\n"); + return; } - free_irq(irq, dev); + pxa_set_cken(ssp_info[dev->port-1].clock, 0); + if (dev->irq) + free_irq(dev->irq, dev); release_mem_region(__PREG(SSCR0_P(dev->port)), 0x2c); + use_count[dev->port - 1]--; + mutex_unlock(&mutex); } EXPORT_SYMBOL(ssp_write_word); @@ -317,3 +329,9 @@ EXPORT_SYMBOL(ssp_save_state); EXPORT_SYMBOL(ssp_restore_state); EXPORT_SYMBOL(ssp_init); EXPORT_SYMBOL(ssp_exit); +EXPORT_SYMBOL(ssp_config); + +MODULE_DESCRIPTION("PXA SSP driver"); +MODULE_AUTHOR("Liam Girdwood"); +MODULE_LICENSE("GPL"); +