| Date: | 2011-06-19 10:57:18 (12 years 5 months ago) |
|---|---|
| Author: | Maarten ter Huurne |
| Commit: | c56a3cefe8e50e1607c9193267eb7b38946879a3 |
| Message: | MMC: JZ4740: Added support for CPU frequency changing. The MSC device clock is stopped before the frequency change. After the change a new divider is computed and the clock is restarted. Also the frequency change is postponed if an I/O operation is in progress. |
| Files: |
drivers/mmc/host/jz4740_mmc.c (6 diffs) |
Change Details
| drivers/mmc/host/jz4740_mmc.c | ||
|---|---|---|
| 23 | 23 | #include <linux/delay.h> |
| 24 | 24 | #include <linux/scatterlist.h> |
| 25 | 25 | #include <linux/clk.h> |
| 26 | #include <linux/cpufreq.h> | |
| 26 | 27 | |
| 27 | 28 | #include <linux/bitops.h> |
| 28 | 29 | #include <linux/gpio.h> |
| ... | ... | |
| 685 | 686 | jz4740_mmc_set_irq_enabled(host, JZ_MMC_IRQ_SDIO, enable); |
| 686 | 687 | } |
| 687 | 688 | |
| 689 | #ifdef CONFIG_CPU_FREQ | |
| 690 | ||
| 691 | static struct jz4740_mmc_host *cpufreq_host; | |
| 692 | ||
| 693 | static int jz4740_mmc_cpufreq_transition(struct notifier_block *nb, | |
| 694 | unsigned long val, void *data) | |
| 695 | { | |
| 696 | struct cpufreq_freqs *freqs = data; | |
| 697 | ||
| 698 | /* TODO: We only have to take action when the PLL freq changes: | |
| 699 | the main dividers have no influence on the MSC device clock. */ | |
| 700 | ||
| 701 | if (val == CPUFREQ_PRECHANGE) { | |
| 702 | mmc_claim_host(cpufreq_host->mmc); | |
| 703 | clk_disable(cpufreq_host->clk); | |
| 704 | } else if (val == CPUFREQ_POSTCHANGE) { | |
| 705 | struct mmc_ios *ios = &cpufreq_host->mmc->ios; | |
| 706 | if (ios->clock) | |
| 707 | jz4740_mmc_set_clock_rate(cpufreq_host, ios->clock); | |
| 708 | if (ios->power_mode != MMC_POWER_OFF) | |
| 709 | clk_enable(cpufreq_host->clk); | |
| 710 | mmc_release_host(cpufreq_host->mmc); | |
| 711 | } | |
| 712 | return 0; | |
| 713 | } | |
| 714 | ||
| 715 | static struct notifier_block jz4740_mmc_cpufreq_nb = { | |
| 716 | .notifier_call = jz4740_mmc_cpufreq_transition, | |
| 717 | }; | |
| 718 | ||
| 719 | static inline int jz4740_mmc_cpufreq_register(struct jz4740_mmc_host *host) | |
| 720 | { | |
| 721 | cpufreq_host = host; | |
| 722 | return cpufreq_register_notifier(&jz4740_mmc_cpufreq_nb, | |
| 723 | CPUFREQ_TRANSITION_NOTIFIER); | |
| 724 | } | |
| 725 | ||
| 726 | static inline void jz4740_mmc_cpufreq_unregister(void) | |
| 727 | { | |
| 728 | cpufreq_unregister_notifier(&jz4740_mmc_cpufreq_nb, | |
| 729 | CPUFREQ_TRANSITION_NOTIFIER); | |
| 730 | } | |
| 731 | ||
| 732 | #else | |
| 733 | ||
| 734 | static inline int jz4740_mmc_cpufreq_register(struct jz4740_mmc_host *host) | |
| 735 | { | |
| 736 | return 0; | |
| 737 | } | |
| 738 | ||
| 739 | static inline void jz4740_mmc_cpufreq_unregister(void) | |
| 740 | { | |
| 741 | } | |
| 742 | ||
| 743 | #endif | |
| 744 | ||
| 688 | 745 | static const struct mmc_host_ops jz4740_mmc_ops = { |
| 689 | 746 | .request = jz4740_mmc_request, |
| 690 | 747 | .set_ios = jz4740_mmc_set_ios, |
| ... | ... | |
| 834 | 891 | goto err_free_host; |
| 835 | 892 | } |
| 836 | 893 | |
| 894 | ret = jz4740_mmc_cpufreq_register(host); | |
| 895 | if (ret) { | |
| 896 | dev_err(&pdev->dev, | |
| 897 | "Failed to register cpufreq transition notifier\n"); | |
| 898 | goto err_clk_put; | |
| 899 | } | |
| 900 | ||
| 837 | 901 | host->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| 838 | 902 | if (!host->mem) { |
| 839 | 903 | ret = -ENOENT; |
| 840 | 904 | dev_err(&pdev->dev, "Failed to get base platform memory\n"); |
| 841 | goto err_clk_put; | |
| 905 | goto err_cpufreq_unreg; | |
| 842 | 906 | } |
| 843 | 907 | |
| 844 | 908 | host->mem = request_mem_region(host->mem->start, |
| ... | ... | |
| 846 | 910 | if (!host->mem) { |
| 847 | 911 | ret = -EBUSY; |
| 848 | 912 | dev_err(&pdev->dev, "Failed to request base memory region\n"); |
| 849 | goto err_clk_put; | |
| 913 | goto err_cpufreq_unreg; | |
| 850 | 914 | } |
| 851 | 915 | |
| 852 | 916 | host->base = ioremap_nocache(host->mem->start, resource_size(host->mem)); |
| ... | ... | |
| 929 | 993 | iounmap(host->base); |
| 930 | 994 | err_release_mem_region: |
| 931 | 995 | release_mem_region(host->mem->start, resource_size(host->mem)); |
| 996 | err_cpufreq_unreg: | |
| 997 | jz4740_mmc_cpufreq_unregister(); | |
| 932 | 998 | err_clk_put: |
| 933 | 999 | clk_put(host->clk); |
| 934 | 1000 | err_free_host: |
| ... | ... | |
| 958 | 1024 | iounmap(host->base); |
| 959 | 1025 | release_mem_region(host->mem->start, resource_size(host->mem)); |
| 960 | 1026 | |
| 1027 | jz4740_mmc_cpufreq_unregister(); | |
| 961 | 1028 | clk_put(host->clk); |
| 962 | 1029 | |
| 963 | 1030 | platform_set_drvdata(pdev, NULL); |
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Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9
