diff options
Diffstat (limited to 'arch/arm/mach-davinci/cdce949.c')
-rw-r--r-- | arch/arm/mach-davinci/cdce949.c | 294 |
1 files changed, 294 insertions, 0 deletions
diff --git a/arch/arm/mach-davinci/cdce949.c b/arch/arm/mach-davinci/cdce949.c new file mode 100644 index 00000000000..ba8b12b2913 --- /dev/null +++ b/arch/arm/mach-davinci/cdce949.c @@ -0,0 +1,294 @@ +/* + * TI CDCE949 clock synthesizer driver + * + * Note: This implementation assumes an input of 27MHz to the CDCE. + * This is by no means constrained by CDCE hardware although the datasheet + * does use this as an example for all illustrations and more importantly: + * that is the crystal input on boards it is currently used on. + * + * Copyright (C) 2009 Texas Instruments Incorporated. http://www.ti.com/ + * + * 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/clk.h> +#include <linux/platform_device.h> +#include <linux/i2c.h> + +#include <mach/clock.h> +#include <mach/cdce949.h> + +#include "clock.h" + +static struct i2c_client *cdce_i2c_client; +static DEFINE_MUTEX(cdce_mutex); + +/* CDCE register descriptor */ +struct cdce_reg { + u8 addr; + u8 val; +}; + +/* Per-Output (Y1, Y2 etc.) frequency descriptor */ +struct cdce_freq { + /* Frequency in KHz */ + unsigned long frequency; + /* + * List of registers to program to obtain a particular frequency. + * 0x0 in register address and value is the end of list marker. + */ + struct cdce_reg *reglist; +}; + +#define CDCE_FREQ_TABLE_ENTRY(line, out) \ +{ \ + .reglist = cdce_y ##line## _ ##out, \ + .frequency = out, \ +} + +/* List of CDCE outputs */ +struct cdce_output { + /* List of frequencies on this output */ + struct cdce_freq *freq_table; + /* Number of possible frequencies */ + int size; +}; + +/* + * Finding out the values to program into CDCE949 registers for a particular + * frequency output is not a simple calculation. Have a look at the datasheet + * for the details. There is desktop software available to help users with + * the calculations. Here, we just depend on the output of that software + * (or hand calculations) instead trying to runtime calculate the register + * values and inflicting misery on ourselves. + */ +static struct cdce_reg cdce_y1_148500[] = { + { 0x13, 0x00 }, + /* program PLL1_0 multiplier */ + { 0x18, 0xaf }, + { 0x19, 0x50 }, + { 0x1a, 0x02 }, + { 0x1b, 0xc9 }, + /* program PLL1_11 multiplier */ + { 0x1c, 0x00 }, + { 0x1d, 0x40 }, + { 0x1e, 0x02 }, + { 0x1f, 0xc9 }, + /* output state selection */ + { 0x15, 0x00 }, + { 0x14, 0xef }, + /* switch MUX to PLL1 output */ + { 0x14, 0x6f }, + { 0x16, 0x06 }, + /* set P2DIV divider, P3DIV and input crystal */ + { 0x17, 0x06 }, + { 0x01, 0x00 }, + { 0x05, 0x48 }, + { 0x02, 0x80 }, + /* enable and disable PLL */ + { 0x02, 0xbc }, + { 0x03, 0x01 }, + { }, +}; + +static struct cdce_reg cdce_y1_74250[] = { + { 0x13, 0x00 }, + { 0x18, 0xaf }, + { 0x19, 0x50 }, + { 0x1a, 0x02 }, + { 0x1b, 0xc9 }, + { 0x1c, 0x00 }, + { 0x1d, 0x40 }, + { 0x1e, 0x02 }, + { 0x1f, 0xc9 }, + /* output state selection */ + { 0x15, 0x00 }, + { 0x14, 0xef }, + /* switch MUX to PLL1 output */ + { 0x14, 0x6f }, + { 0x16, 0x06 }, + /* set P2DIV divider, P3DIV and input crystal */ + { 0x17, 0x06 }, + { 0x01, 0x00 }, + { 0x05, 0x48 }, + { 0x02, 0x80 }, + /* enable and disable PLL */ + { 0x02, 0xbc }, + { 0x03, 0x02 }, + { }, +}; + +static struct cdce_reg cdce_y1_27000[] = { + { 0x13, 0x00 }, + { 0x18, 0x00 }, + { 0x19, 0x40 }, + { 0x1a, 0x02 }, + { 0x1b, 0x08 }, + { 0x1c, 0x00 }, + { 0x1d, 0x40 }, + { 0x1e, 0x02 }, + { 0x1f, 0x08 }, + { 0x15, 0x02 }, + { 0x14, 0xed }, + { 0x16, 0x01 }, + { 0x17, 0x01 }, + { 0x01, 0x00 }, + { 0x05, 0x50 }, + { 0x02, 0xb4 }, + { 0x03, 0x01 }, + { }, +}; + +static struct cdce_freq cdce_y1_freqs[] = { + CDCE_FREQ_TABLE_ENTRY(1, 148500), + CDCE_FREQ_TABLE_ENTRY(1, 74250), + CDCE_FREQ_TABLE_ENTRY(1, 27000), +}; + +static struct cdce_reg cdce_y5_13500[] = { + { 0x27, 0x08 }, + { 0x28, 0x00 }, + { 0x29, 0x40 }, + { 0x2a, 0x02 }, + { 0x2b, 0x08 }, + { 0x24, 0x6f }, + { }, +}; + +static struct cdce_reg cdce_y5_16875[] = { + { 0x27, 0x08 }, + { 0x28, 0x9f }, + { 0x29, 0xb0 }, + { 0x2a, 0x02 }, + { 0x2b, 0x89 }, + { 0x24, 0x6f }, + { }, +}; + +static struct cdce_reg cdce_y5_27000[] = { + { 0x27, 0x04 }, + { 0x28, 0x00 }, + { 0x29, 0x40 }, + { 0x2a, 0x02 }, + { 0x2b, 0x08 }, + { 0x24, 0x6f }, + { }, +}; +static struct cdce_reg cdce_y5_54000[] = { + { 0x27, 0x04 }, + { 0x28, 0xff }, + { 0x29, 0x80 }, + { 0x2a, 0x02 }, + { 0x2b, 0x07 }, + { 0x24, 0x6f }, + { }, +}; + +static struct cdce_reg cdce_y5_81000[] = { + { 0x27, 0x02 }, + { 0x28, 0xbf }, + { 0x29, 0xa0 }, + { 0x2a, 0x03 }, + { 0x2b, 0x0a }, + { 0x24, 0x6f }, + { }, +}; + +static struct cdce_freq cdce_y5_freqs[] = { + CDCE_FREQ_TABLE_ENTRY(5, 13500), + CDCE_FREQ_TABLE_ENTRY(5, 16875), + CDCE_FREQ_TABLE_ENTRY(5, 27000), + CDCE_FREQ_TABLE_ENTRY(5, 54000), + CDCE_FREQ_TABLE_ENTRY(5, 81000), +}; + + +static struct cdce_output output_list[] = { + [1] = { cdce_y1_freqs, ARRAY_SIZE(cdce_y1_freqs) }, + [5] = { cdce_y5_freqs, ARRAY_SIZE(cdce_y5_freqs) }, +}; + +int cdce_set_rate(struct clk *clk, unsigned long rate) +{ + int i, ret = 0; + struct cdce_freq *freq_table = output_list[clk->lpsc].freq_table; + struct cdce_reg *regs = NULL; + + if (!cdce_i2c_client) + return -ENODEV; + + if (!freq_table) + return -EINVAL; + + for (i = 0; i < output_list[clk->lpsc].size; i++) { + if (freq_table[i].frequency == rate / 1000) { + regs = freq_table[i].reglist; + break; + } + } + + if (!regs) + return -EINVAL; + + mutex_lock(&cdce_mutex); + for (i = 0; regs[i].addr; i++) { + ret = i2c_smbus_write_byte_data(cdce_i2c_client, + regs[i].addr | 0x80, regs[i].val); + if (ret) + break; + } + mutex_unlock(&cdce_mutex); + + if (!ret) + clk->rate = rate; + + return ret; +} + +static int cdce_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + cdce_i2c_client = client; + return 0; +} + +static int __devexit cdce_remove(struct i2c_client *client) +{ + cdce_i2c_client = NULL; + return 0; +} + +static const struct i2c_device_id cdce_id[] = { + {"cdce949", 0}, + {}, +}; +MODULE_DEVICE_TABLE(i2c, cdce_id); + +static struct i2c_driver cdce_driver = { + .driver = { + .owner = THIS_MODULE, + .name = "cdce949", + }, + .probe = cdce_probe, + .remove = __devexit_p(cdce_remove), + .id_table = cdce_id, +}; + +static int __init cdce_init(void) +{ + return i2c_add_driver(&cdce_driver); +} +subsys_initcall(cdce_init); + +static void __exit cdce_exit(void) +{ + i2c_del_driver(&cdce_driver); +} +module_exit(cdce_exit); + +MODULE_AUTHOR("Texas Instruments"); +MODULE_DESCRIPTION("CDCE949 clock synthesizer driver"); +MODULE_LICENSE("GPL v2"); |