diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-06-06 19:35:10 -0400 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-06-06 19:35:10 -0400 |
| commit | 57d326169e878a1a37b2bccd1cf81f6809ee67b9 (patch) | |
| tree | 86ed74ae4dc2beaebce1c67b8459f1873b777d3a /drivers/rtc/rtc-mcp795.c | |
| parent | 7b215de3d0abbc4f6daf2efd19e8809af0564490 (diff) | |
| parent | 0244756edc4b98c129e92c7061d9f383708cf786 (diff) | |
Merge branch 'akpm' (patches from Andrew Morton) into next
Merge more updates from Andrew Morton:
- Most of the rest of MM.
This includes "mark remap_file_pages syscall as deprecated" but the
actual "replace remap_file_pages syscall with emulation" is held
back. I guess we'll need to work out when to pull the trigger on
that one.
- various minor cleanups to obscure filesystems
- the drivers/rtc queue
- hfsplus updates
- ufs, hpfs, fatfs, affs, reiserfs
- Documentation/
- signals
- procfs
- cpu hotplug
- lib/idr.c
- rapidio
- sysctl
- ipc updates
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (171 commits)
ufs: sb mutex merge + mutex_destroy
powerpc: update comments for generic idle conversion
cris: update comments for generic idle conversion
idle: remove cpu_idle() forward declarations
nbd: zero from and len fields in NBD_CMD_DISCONNECT.
mm: convert some level-less printks to pr_*
MAINTAINERS: adi-buildroot-devel is moderated
MAINTAINERS: add linux-api for review of API/ABI changes
mm/kmemleak-test.c: use pr_fmt for logging
fs/dlm/debug_fs.c: replace seq_printf by seq_puts
fs/dlm/lockspace.c: convert simple_str to kstr
fs/dlm/config.c: convert simple_str to kstr
mm: mark remap_file_pages() syscall as deprecated
mm: memcontrol: remove unnecessary memcg argument from soft limit functions
mm: memcontrol: clean up memcg zoneinfo lookup
mm/memblock.c: call kmemleak directly from memblock_(alloc|free)
mm/mempool.c: update the kmemleak stack trace for mempool allocations
lib/radix-tree.c: update the kmemleak stack trace for radix tree allocations
mm: introduce kmemleak_update_trace()
mm/kmemleak.c: use %u to print ->checksum
...
Diffstat (limited to 'drivers/rtc/rtc-mcp795.c')
| -rw-r--r-- | drivers/rtc/rtc-mcp795.c | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-mcp795.c b/drivers/rtc/rtc-mcp795.c new file mode 100644 index 000000000000..34295bf00416 --- /dev/null +++ b/drivers/rtc/rtc-mcp795.c | |||
| @@ -0,0 +1,199 @@ | |||
| 1 | /* | ||
| 2 | * SPI Driver for Microchip MCP795 RTC | ||
| 3 | * | ||
| 4 | * Copyright (C) Josef Gajdusek <atx@atx.name> | ||
| 5 | * | ||
| 6 | * based on other Linux RTC drivers | ||
| 7 | * | ||
| 8 | * Device datasheet: | ||
| 9 | * http://ww1.microchip.com/downloads/en/DeviceDoc/22280A.pdf | ||
| 10 | * | ||
| 11 | * This program is free software; you can redistribute it and/or modify | ||
| 12 | * it under the terms of the GNU General Public License version 2 as | ||
| 13 | * published by the Free Software Foundation. | ||
| 14 | * | ||
| 15 | * */ | ||
| 16 | |||
| 17 | #include <linux/module.h> | ||
| 18 | #include <linux/kernel.h> | ||
| 19 | #include <linux/device.h> | ||
| 20 | #include <linux/printk.h> | ||
| 21 | #include <linux/spi/spi.h> | ||
| 22 | #include <linux/rtc.h> | ||
| 23 | |||
| 24 | /* MCP795 Instructions, see datasheet table 3-1 */ | ||
| 25 | #define MCP795_EEREAD 0x03 | ||
| 26 | #define MCP795_EEWRITE 0x02 | ||
| 27 | #define MCP795_EEWRDI 0x04 | ||
| 28 | #define MCP795_EEWREN 0x06 | ||
| 29 | #define MCP795_SRREAD 0x05 | ||
| 30 | #define MCP795_SRWRITE 0x01 | ||
| 31 | #define MCP795_READ 0x13 | ||
| 32 | #define MCP795_WRITE 0x12 | ||
| 33 | #define MCP795_UNLOCK 0x14 | ||
| 34 | #define MCP795_IDWRITE 0x32 | ||
| 35 | #define MCP795_IDREAD 0x33 | ||
| 36 | #define MCP795_CLRWDT 0x44 | ||
| 37 | #define MCP795_CLRRAM 0x54 | ||
| 38 | |||
| 39 | #define MCP795_ST_BIT 0x80 | ||
| 40 | #define MCP795_24_BIT 0x40 | ||
| 41 | |||
| 42 | static int mcp795_rtcc_read(struct device *dev, u8 addr, u8 *buf, u8 count) | ||
| 43 | { | ||
| 44 | struct spi_device *spi = to_spi_device(dev); | ||
| 45 | int ret; | ||
| 46 | u8 tx[2]; | ||
| 47 | |||
| 48 | tx[0] = MCP795_READ; | ||
| 49 | tx[1] = addr; | ||
| 50 | ret = spi_write_then_read(spi, tx, sizeof(tx), buf, count); | ||
| 51 | |||
| 52 | if (ret) | ||
| 53 | dev_err(dev, "Failed reading %d bytes from address %x.\n", | ||
| 54 | count, addr); | ||
| 55 | |||
| 56 | return ret; | ||
| 57 | } | ||
| 58 | |||
| 59 | static int mcp795_rtcc_write(struct device *dev, u8 addr, u8 *data, u8 count) | ||
| 60 | { | ||
| 61 | struct spi_device *spi = to_spi_device(dev); | ||
| 62 | int ret; | ||
| 63 | u8 tx[2 + count]; | ||
| 64 | |||
| 65 | tx[0] = MCP795_WRITE; | ||
| 66 | tx[1] = addr; | ||
| 67 | memcpy(&tx[2], data, count); | ||
| 68 | |||
| 69 | ret = spi_write(spi, tx, 2 + count); | ||
| 70 | |||
| 71 | if (ret) | ||
| 72 | dev_err(dev, "Failed to write %d bytes to address %x.\n", | ||
| 73 | count, addr); | ||
| 74 | |||
| 75 | return ret; | ||
| 76 | } | ||
| 77 | |||
| 78 | static int mcp795_rtcc_set_bits(struct device *dev, u8 addr, u8 mask, u8 state) | ||
| 79 | { | ||
| 80 | int ret; | ||
| 81 | u8 tmp; | ||
| 82 | |||
| 83 | ret = mcp795_rtcc_read(dev, addr, &tmp, 1); | ||
| 84 | if (ret) | ||
| 85 | return ret; | ||
| 86 | |||
| 87 | if ((tmp & mask) != state) { | ||
| 88 | tmp = (tmp & ~mask) | state; | ||
| 89 | ret = mcp795_rtcc_write(dev, addr, &tmp, 1); | ||
| 90 | } | ||
| 91 | |||
| 92 | return ret; | ||
| 93 | } | ||
| 94 | |||
| 95 | static int mcp795_set_time(struct device *dev, struct rtc_time *tim) | ||
| 96 | { | ||
| 97 | int ret; | ||
| 98 | u8 data[7]; | ||
| 99 | |||
| 100 | /* Read first, so we can leave config bits untouched */ | ||
| 101 | ret = mcp795_rtcc_read(dev, 0x01, data, sizeof(data)); | ||
| 102 | |||
| 103 | if (ret) | ||
| 104 | return ret; | ||
| 105 | |||
| 106 | data[0] = (data[0] & 0x80) | ((tim->tm_sec / 10) << 4) | (tim->tm_sec % 10); | ||
| 107 | data[1] = (data[1] & 0x80) | ((tim->tm_min / 10) << 4) | (tim->tm_min % 10); | ||
| 108 | data[2] = ((tim->tm_hour / 10) << 4) | (tim->tm_hour % 10); | ||
| 109 | data[4] = ((tim->tm_mday / 10) << 4) | ((tim->tm_mday) % 10); | ||
| 110 | data[5] = (data[5] & 0x10) | (tim->tm_mon / 10) | (tim->tm_mon % 10); | ||
| 111 | |||
| 112 | if (tim->tm_year > 100) | ||
| 113 | tim->tm_year -= 100; | ||
| 114 | |||
| 115 | data[6] = ((tim->tm_year / 10) << 4) | (tim->tm_year % 10); | ||
| 116 | |||
| 117 | ret = mcp795_rtcc_write(dev, 0x01, data, sizeof(data)); | ||
| 118 | |||
| 119 | if (ret) | ||
| 120 | return ret; | ||
| 121 | |||
| 122 | dev_dbg(dev, "Set mcp795: %04d-%02d-%02d %02d:%02d:%02d\n", | ||
| 123 | tim->tm_year + 1900, tim->tm_mon, tim->tm_mday, | ||
| 124 | tim->tm_hour, tim->tm_min, tim->tm_sec); | ||
| 125 | |||
| 126 | return 0; | ||
| 127 | } | ||
| 128 | |||
| 129 | static int mcp795_read_time(struct device *dev, struct rtc_time *tim) | ||
| 130 | { | ||
| 131 | int ret; | ||
| 132 | u8 data[7]; | ||
| 133 | |||
| 134 | ret = mcp795_rtcc_read(dev, 0x01, data, sizeof(data)); | ||
| 135 | |||
| 136 | if (ret) | ||
| 137 | return ret; | ||
| 138 | |||
| 139 | tim->tm_sec = ((data[0] & 0x70) >> 4) * 10 + (data[0] & 0x0f); | ||
| 140 | tim->tm_min = ((data[1] & 0x70) >> 4) * 10 + (data[1] & 0x0f); | ||
| 141 | tim->tm_hour = ((data[2] & 0x30) >> 4) * 10 + (data[2] & 0x0f); | ||
| 142 | tim->tm_mday = ((data[4] & 0x30) >> 4) * 10 + (data[4] & 0x0f); | ||
| 143 | tim->tm_mon = ((data[5] & 0x10) >> 4) * 10 + (data[5] & 0x0f); | ||
| 144 | tim->tm_year = ((data[6] & 0xf0) >> 4) * 10 + (data[6] & 0x0f) + 100; /* Assume we are in 20xx */ | ||
| 145 | |||
| 146 | dev_dbg(dev, "Read from mcp795: %04d-%02d-%02d %02d:%02d:%02d\n", | ||
| 147 | tim->tm_year + 1900, tim->tm_mon, tim->tm_mday, | ||
| 148 | tim->tm_hour, tim->tm_min, tim->tm_sec); | ||
| 149 | |||
| 150 | return rtc_valid_tm(tim); | ||
| 151 | } | ||
| 152 | |||
| 153 | static struct rtc_class_ops mcp795_rtc_ops = { | ||
| 154 | .read_time = mcp795_read_time, | ||
| 155 | .set_time = mcp795_set_time | ||
| 156 | }; | ||
| 157 | |||
| 158 | static int mcp795_probe(struct spi_device *spi) | ||
| 159 | { | ||
| 160 | struct rtc_device *rtc; | ||
| 161 | int ret; | ||
| 162 | |||
| 163 | spi->mode = SPI_MODE_0; | ||
| 164 | spi->bits_per_word = 8; | ||
| 165 | ret = spi_setup(spi); | ||
| 166 | if (ret) { | ||
| 167 | dev_err(&spi->dev, "Unable to setup SPI\n"); | ||
| 168 | return ret; | ||
| 169 | } | ||
| 170 | |||
| 171 | /* Start the oscillator */ | ||
| 172 | mcp795_rtcc_set_bits(&spi->dev, 0x01, MCP795_ST_BIT, MCP795_ST_BIT); | ||
| 173 | /* Clear the 12 hour mode flag*/ | ||
| 174 | mcp795_rtcc_set_bits(&spi->dev, 0x03, MCP795_24_BIT, 0); | ||
| 175 | |||
| 176 | rtc = devm_rtc_device_register(&spi->dev, "rtc-mcp795", | ||
| 177 | &mcp795_rtc_ops, THIS_MODULE); | ||
| 178 | if (IS_ERR(rtc)) | ||
| 179 | return PTR_ERR(rtc); | ||
| 180 | |||
| 181 | spi_set_drvdata(spi, rtc); | ||
| 182 | |||
| 183 | return 0; | ||
| 184 | } | ||
| 185 | |||
| 186 | static struct spi_driver mcp795_driver = { | ||
| 187 | .driver = { | ||
| 188 | .name = "rtc-mcp795", | ||
| 189 | .owner = THIS_MODULE, | ||
| 190 | }, | ||
| 191 | .probe = mcp795_probe, | ||
| 192 | }; | ||
| 193 | |||
| 194 | module_spi_driver(mcp795_driver); | ||
| 195 | |||
| 196 | MODULE_DESCRIPTION("MCP795 RTC SPI Driver"); | ||
| 197 | MODULE_AUTHOR("Josef Gajdusek <atx@atx.name>"); | ||
| 198 | MODULE_LICENSE("GPL"); | ||
| 199 | MODULE_ALIAS("spi:mcp795"); | ||
