| /* |
| * (C) Copyright 2010 Quantenna Communications Inc. |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License as |
| * published by the Free Software Foundation; either version 2 of |
| * the License, or (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, |
| * MA 02111-1307 USA |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/io.h> |
| #include <linux/device.h> |
| #include <linux/err.h> |
| #include <asm/hardware.h> |
| #include <asm/board/platform.h> |
| |
| struct clk { |
| unsigned long rate; /* Clock rate in HZ */ |
| }; |
| |
| struct qtn_clk_lookup_entry { |
| const char *name; |
| struct clk *clk_p; |
| }; |
| |
| static struct clk qtn_clk_bus = { |
| .rate = 0, |
| }; |
| |
| static struct qtn_clk_lookup_entry qtn_clk_list[] = { |
| { .name = "qtn-i2c.0", .clk_p = &qtn_clk_bus }, |
| { .name = "bus-clk", .clk_p = &qtn_clk_bus }, |
| }; |
| |
| static unsigned long qtn_clk_get_bus_freq(void) |
| { |
| unsigned long freq = 0; |
| |
| #ifdef CONFIG_ARC700_FPGA |
| freq = CONFIG_ARC700_FPGA_CLK; |
| #else |
| switch(readl(IO_ADDRESS(RUBY_SYS_CTL_CTRL)) & RUBY_SYS_CTL_MASK_CLKSEL) { |
| case RUBY_SYS_CTL_CLKSEL(0x0): |
| freq = RUBY_SYS_CTL_CLKSEL_00_BUS_FREQ; |
| break; |
| case RUBY_SYS_CTL_CLKSEL(0x1): |
| freq = RUBY_SYS_CTL_CLKSEL_01_BUS_FREQ; |
| break; |
| case RUBY_SYS_CTL_CLKSEL(0x2): |
| freq = RUBY_SYS_CTL_CLKSEL_10_BUS_FREQ; |
| break; |
| case RUBY_SYS_CTL_CLKSEL(0x3): |
| freq = RUBY_SYS_CTL_CLKSEL_11_BUS_FREQ; |
| break; |
| default: |
| panic("Logic error!\n"); |
| break; |
| } |
| #endif |
| return freq; |
| } |
| |
| static int __init qtn_clk_init_rates(void) |
| { |
| /* Clock source bits are latched on power-on */ |
| qtn_clk_bus.rate = qtn_clk_get_bus_freq(); |
| return 0; |
| } |
| |
| arch_initcall(qtn_clk_init_rates); |
| |
| |
| struct clk *clk_get(struct device *dev, const char *id) |
| { |
| struct clk *ret_clk = NULL; |
| const char *dev_id = NULL; |
| int i; |
| |
| if (dev) { |
| dev_id = dev_name(dev); |
| |
| for (i = 0; i < ARRAY_SIZE(qtn_clk_list); ++i) { |
| if (!strcmp(dev_id, qtn_clk_list[i].name)) { |
| ret_clk = qtn_clk_list[i].clk_p; |
| break; |
| } |
| } |
| } |
| |
| return ret_clk ? ret_clk : ERR_PTR(-ENOENT); |
| } |
| EXPORT_SYMBOL(clk_get); |
| |
| unsigned long clk_get_rate(struct clk *clk) |
| { |
| return clk ? clk->rate : 0; |
| } |
| EXPORT_SYMBOL(clk_get_rate); |