diff options
Diffstat (limited to 'drivers/misc/atmel_tclib.c')
| -rw-r--r-- | drivers/misc/atmel_tclib.c | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/drivers/misc/atmel_tclib.c b/drivers/misc/atmel_tclib.c new file mode 100644 index 000000000000..05dc8a31f280 --- /dev/null +++ b/drivers/misc/atmel_tclib.c | |||
| @@ -0,0 +1,161 @@ | |||
| 1 | #include <linux/atmel_tc.h> | ||
| 2 | #include <linux/clk.h> | ||
| 3 | #include <linux/err.h> | ||
| 4 | #include <linux/init.h> | ||
| 5 | #include <linux/io.h> | ||
| 6 | #include <linux/ioport.h> | ||
| 7 | #include <linux/kernel.h> | ||
| 8 | #include <linux/platform_device.h> | ||
| 9 | |||
| 10 | /* Number of bytes to reserve for the iomem resource */ | ||
| 11 | #define ATMEL_TC_IOMEM_SIZE 256 | ||
| 12 | |||
| 13 | |||
| 14 | /* | ||
| 15 | * This is a thin library to solve the problem of how to portably allocate | ||
| 16 | * one of the TC blocks. For simplicity, it doesn't currently expect to | ||
| 17 | * share individual timers between different drivers. | ||
| 18 | */ | ||
| 19 | |||
| 20 | #if defined(CONFIG_AVR32) | ||
| 21 | /* AVR32 has these divide PBB */ | ||
| 22 | const u8 atmel_tc_divisors[5] = { 0, 4, 8, 16, 32, }; | ||
| 23 | EXPORT_SYMBOL(atmel_tc_divisors); | ||
| 24 | |||
| 25 | #elif defined(CONFIG_ARCH_AT91) | ||
| 26 | /* AT91 has these divide MCK */ | ||
| 27 | const u8 atmel_tc_divisors[5] = { 2, 8, 32, 128, 0, }; | ||
| 28 | EXPORT_SYMBOL(atmel_tc_divisors); | ||
| 29 | |||
| 30 | #endif | ||
| 31 | |||
| 32 | static DEFINE_SPINLOCK(tc_list_lock); | ||
| 33 | static LIST_HEAD(tc_list); | ||
| 34 | |||
| 35 | /** | ||
| 36 | * atmel_tc_alloc - allocate a specified TC block | ||
| 37 | * @block: which block to allocate | ||
| 38 | * @name: name to be associated with the iomem resource | ||
| 39 | * | ||
| 40 | * Caller allocates a block. If it is available, a pointer to a | ||
| 41 | * pre-initialized struct atmel_tc is returned. The caller can access | ||
| 42 | * the registers directly through the "regs" field. | ||
| 43 | */ | ||
| 44 | struct atmel_tc *atmel_tc_alloc(unsigned block, const char *name) | ||
| 45 | { | ||
| 46 | struct atmel_tc *tc; | ||
| 47 | struct platform_device *pdev = NULL; | ||
| 48 | struct resource *r; | ||
| 49 | |||
| 50 | spin_lock(&tc_list_lock); | ||
| 51 | list_for_each_entry(tc, &tc_list, node) { | ||
| 52 | if (tc->pdev->id == block) { | ||
| 53 | pdev = tc->pdev; | ||
| 54 | break; | ||
| 55 | } | ||
| 56 | } | ||
| 57 | |||
| 58 | if (!pdev || tc->iomem) | ||
| 59 | goto fail; | ||
| 60 | |||
| 61 | r = platform_get_resource(pdev, IORESOURCE_MEM, 0); | ||
| 62 | r = request_mem_region(r->start, ATMEL_TC_IOMEM_SIZE, name); | ||
| 63 | if (!r) | ||
| 64 | goto fail; | ||
| 65 | |||
| 66 | tc->regs = ioremap(r->start, ATMEL_TC_IOMEM_SIZE); | ||
| 67 | if (!tc->regs) | ||
| 68 | goto fail_ioremap; | ||
| 69 | |||
| 70 | tc->iomem = r; | ||
| 71 | |||
| 72 | out: | ||
| 73 | spin_unlock(&tc_list_lock); | ||
| 74 | return tc; | ||
| 75 | |||
| 76 | fail_ioremap: | ||
| 77 | release_resource(r); | ||
| 78 | fail: | ||
| 79 | tc = NULL; | ||
| 80 | goto out; | ||
| 81 | } | ||
| 82 | EXPORT_SYMBOL_GPL(atmel_tc_alloc); | ||
| 83 | |||
| 84 | /** | ||
| 85 | * atmel_tc_free - release a specified TC block | ||
| 86 | * @tc: Timer/counter block that was returned by atmel_tc_alloc() | ||
| 87 | * | ||
| 88 | * This reverses the effect of atmel_tc_alloc(), unmapping the I/O | ||
| 89 | * registers, invalidating the resource returned by that routine and | ||
| 90 | * making the TC available to other drivers. | ||
| 91 | */ | ||
| 92 | void atmel_tc_free(struct atmel_tc *tc) | ||
| 93 | { | ||
| 94 | spin_lock(&tc_list_lock); | ||
| 95 | if (tc->regs) { | ||
| 96 | iounmap(tc->regs); | ||
| 97 | release_resource(tc->iomem); | ||
| 98 | tc->regs = NULL; | ||
| 99 | tc->iomem = NULL; | ||
| 100 | } | ||
| 101 | spin_unlock(&tc_list_lock); | ||
| 102 | } | ||
| 103 | EXPORT_SYMBOL_GPL(atmel_tc_free); | ||
| 104 | |||
| 105 | static int __init tc_probe(struct platform_device *pdev) | ||
| 106 | { | ||
| 107 | struct atmel_tc *tc; | ||
| 108 | struct clk *clk; | ||
| 109 | int irq; | ||
| 110 | |||
| 111 | if (!platform_get_resource(pdev, IORESOURCE_MEM, 0)) | ||
| 112 | return -EINVAL; | ||
| 113 | |||
| 114 | irq = platform_get_irq(pdev, 0); | ||
| 115 | if (irq < 0) | ||
| 116 | return -EINVAL; | ||
| 117 | |||
| 118 | tc = kzalloc(sizeof(struct atmel_tc), GFP_KERNEL); | ||
| 119 | if (!tc) | ||
| 120 | return -ENOMEM; | ||
| 121 | |||
| 122 | tc->pdev = pdev; | ||
| 123 | |||
| 124 | clk = clk_get(&pdev->dev, "t0_clk"); | ||
| 125 | if (IS_ERR(clk)) { | ||
| 126 | kfree(tc); | ||
| 127 | return -EINVAL; | ||
| 128 | } | ||
| 129 | |||
| 130 | tc->clk[0] = clk; | ||
| 131 | tc->clk[1] = clk_get(&pdev->dev, "t1_clk"); | ||
| 132 | if (IS_ERR(tc->clk[1])) | ||
| 133 | tc->clk[1] = clk; | ||
| 134 | tc->clk[2] = clk_get(&pdev->dev, "t2_clk"); | ||
| 135 | if (IS_ERR(tc->clk[2])) | ||
| 136 | tc->clk[2] = clk; | ||
| 137 | |||
| 138 | tc->irq[0] = irq; | ||
| 139 | tc->irq[1] = platform_get_irq(pdev, 1); | ||
| 140 | if (tc->irq[1] < 0) | ||
| 141 | tc->irq[1] = irq; | ||
| 142 | tc->irq[2] = platform_get_irq(pdev, 2); | ||
| 143 | if (tc->irq[2] < 0) | ||
| 144 | tc->irq[2] = irq; | ||
| 145 | |||
| 146 | spin_lock(&tc_list_lock); | ||
| 147 | list_add_tail(&tc->node, &tc_list); | ||
| 148 | spin_unlock(&tc_list_lock); | ||
| 149 | |||
| 150 | return 0; | ||
| 151 | } | ||
| 152 | |||
| 153 | static struct platform_driver tc_driver = { | ||
| 154 | .driver.name = "atmel_tcb", | ||
| 155 | }; | ||
| 156 | |||
| 157 | static int __init tc_init(void) | ||
| 158 | { | ||
| 159 | return platform_driver_probe(&tc_driver, tc_probe); | ||
| 160 | } | ||
| 161 | arch_initcall(tc_init); | ||
