zzj
1
/pt.c/
#include<linux/pwm.h>
#include<linux/init.h>
#include<linux/module.h>
#include <linux/kernel.h>
#include <linux/delay.h>
MODULE_LICENSE(“GPL”);
struct pwm_device * pwm1 = NULL;
static int __init pwm_init(void)
{
pwm1 = pwm_request(1, “backlight-pwm”);
pwm_config(pwm1, 100000, 500000);
printk(“success\n”);
pwm_enable(pwm1);
return 0;
}
static void __exit pwm_exit(void)
{
printk(“Exit pwm\n”);
}
subsys_initcall(pwm_init);
module_exit(pwm_exit);
firefly@firefly:~/temp/makepra/pwm$ dmesg|tail
[ 127.675031] bfa0: 814f4e00 c000da00 be97a6f4 be97a874 00000003 b6f85398 00000000 00000000
[ 127.675044] bfc0: be97a6f4 be97a874 814f4e00 0000017b b6f91e08 00000000 b6f81b60 00000000
[ 127.675057] bfe0: be97a6a0 be97a690 b6f7c177 b6eec982 80030030 00000003 00000000 00000000
[ 127.675081] [] (pwm_config+0x40/0x60) from [] (pwm_init+0x24/0x50 [pt])
[ 127.675105] [] (pwm_init+0x24/0x50 [pt]) from [] (do_one_initcall+0x34/0xc8)
[ 127.675126] [] (do_one_initcall+0x34/0xc8) from [] (do_init_module+0x44/0x168)
[ 127.675144] [] (do_init_module+0x44/0x168) from [] (SyS_finit_module+0x6c/0x94)
[ 127.675164] [] (SyS_finit_module+0x6c/0x94) from [] (ret_fast_syscall+0x0/0x30)
[ 127.675177] Code: e1540003 c3822001 e3520000 1a000005 (e5910010)
[ 127.675258] —[ end trace 0be8b8afa4266cfb ]—
zzj
2
还有就是注册pwm-rockchip.c这个驱动文件的具体步骤是什么
leung
3
zzj 发表于 2016-8-26 14:12
还有就是注册pwm-rockchip.c这个驱动文件的具体步骤是什么
无法申请应该具体看pwm_request报什么问题，一般申请不了都是占用，检查一下dts，那里也用到了pwm1
zzj
4
leung先森 发表于 2016-8-26 14:35
无法申请应该具体看pwm_request报什么问题，一般申请不了都是占用，检查一下dts，那里也用到了pwm1
请问怎么检查dts?检查出来后又要怎么释放？用pwm_free()吗
检查dts中是否被占用，disabled掉 pwm_request申请失败表明pwm1已经被占用，你可以直接操作它。若想自己另写驱动，那只能在sts中disabled，然后自己添加
zzj
6
HelloBirthday 发表于 2016-8-26 16:11
检查dts中是否被占用，disabled掉 pwm_request申请失败表明pwm1已经被占用，你可以直接操作它。若想 …
我把firefly rk3288.dts里和rk3288.dtsi里的pwm都设置成okay，然后跟你说的一样直接操作pwm1，函数调用顺序是struct pwm_device * pwm1;pwm_enable(pwm1);pwm_config(pwm1,100000,500000);
然后用示波器测pwm1口，结果没有电压变化，还是搞不明白:'(
zzj
8
xaityyy 发表于 2016-8-28 15:38
dmesg给全呀。log太少了
没办法
，用的dmesg|tail命令只给这些
用dmesg的话就给的超出屏幕
dmesg | tee dmesg.log。然后发dmesg.log出来。
如果是串口，打开log，就会有log到本地。
pwm_regulator {
compatible = “rockchip_pwm_regulator”;
pwms = <&pwm1 0 2000>;
rockchip,pwm_id= <1>;
rockchip,pwm_voltage_map= <925000 950000 975000 1000000 1025000 1050000 1075000 1100000 1125000 1150000 1175000 1200000 1225000 1250000 1275000 1300000 1325000 1350000 1375000 1400000>;
rockchip,pwm_voltage= <1100000>;
rockchip,pwm_min_voltage= <925000>;
rockchip,pwm_max_voltage= <1400000>;
rockchip,pwm_suspend_voltage= <950000>;
rockchip,pwm_coefficient= <475>;
regulators {
#address-cells = <1>;
#size-cells = <0>;
pwm_reg0: regulator@0 {
regulator-compatible = “pwm_dcdc1”;
regulator-name= “vdd_logic”;
regulator-min-microvolt = <925000>;
regulator-max-microvolt = <1400000>;
regulator-always-on;
regulator-boot-on;
};
};
};
dts中有这么一段,好像已经占用了pwm1,所以申请会失败,
但是这个是用来做电源控制吗,对应的硬件设备是什么?
zzj
11
长的 发表于 2016-8-30 10:16
pwm_regulator {
compatible = “rockchip_pwm_regulator”;
pwms = ;
我看wiki里面是控制什么backlight的，但是就算我全部都设为disabled还是无法申请，对应的硬件设备是你自己接LCD时的屏幕背光
zzj
12
xaityyy 发表于 2016-8-28 16:21
dmesg | tee dmesg.log。然后发dmesg.log出来。
如果是串口，打开log，就会有log到本地。
是这个吗 我选了一段跟申请有关的
[ 2.300069] init success
[ 2.300247] probe device ff9c0000.hevc_service
[ 2.300856] hevc_service: power on
[ 2.301996] checking hw id 6867
[ 2.302857] vcodec hevc_service: vcodec ion client create success!
[ 2.303753] hevc_service: power off…
[ 2.303855] done
[ 2.303909] init success
[ 2.304279] rknandbase v1.0 2014-03-31
[ 2.304906] rknand_probe clk rate = 148500000
[ 2.305302] rknand_driver:ret = 0
[ 2.306411] audit: initializing netlink socket (disabled)
[ 2.306553] type=2000 audit(1.270:1): initialized
[ 2.309435] bounce pool size: 64 pages
[ 2.324875] fuse init (API version 7.22)
[ 2.326121] msgmni has been set to 1424
[ 2.326307] SELinux: Registering netfilter hooks
[ 2.332471] Block layer SCSI generic (bsg) driver version 0.4 loaded (major 246)
[ 2.332571] io scheduler noop registered
[ 2.332630] io scheduler deadline registered
[ 2.332971] io scheduler cfq registered (default)
[ 2.334435] Console: switching to colour frame buffer device 240x67
[ 2.383801] rga ff920000.rga: rga ion client create success!
[ 2.384451] rga: Driver loaded succesfully
[ 2.386058] IEP Power ON
[ 2.386290] iep ion client create success!
[ 2.387440] rk_iommu ff900800.iep_mmu: (iep) Enabled
[ 2.387697] rk_iommu ff900800.iep_mmu: rockchip_iommu_attach_device: Attached new IOMMU with pgtable 0x2e244000
[ 2.387796] IEP Power OFF
[ 2.387962] rk_iommu ff900800.iep_mmu: (iep) Disabled
[ 2.388210] rk_iommu ff900800.iep_mmu: rockchip_iommu_detach_device: Detached IOMMU with pgtable 0x2e244000
[ 2.388635] IEP Driver loaded succesfully
[ 2.389093] Module initialized.
[ 2.391763] dma-pl330 ffb20000.pdma: Loaded driver for PL330 DMAC-2364208
[ 2.392107] dma-pl330 ffb20000.pdma: DBUFF-64x8bytes Num_Chans-5 Num_Peri-6 Num_Events-10
[ 2.396826] dma-pl330 ff250000.pdma: Loaded driver for PL330 DMAC-2364208
[ 2.397169] dma-pl330 ff250000.pdma: DBUFF-128x8bytes Num_Chans-8 Num_Peri-20 Num_Events-16
[ 2.398304] pwm-voltage-regulator pwm_regulator.22: unable to request PWM, trying legacy API
[ 2.398695] pwm-voltage-regulator pwm_regulator.22: unable to request legacy PWM
[ 2.399018] pwm_regulator_probe:error
[ 2.399235] platform pwm_regulator.22: Driver pwm-voltage-regulator requests probe deferral
[ 2.400625] rk_serial.c v1.8 2014-03-04
[ 2.401434] ff180000.serial: ttyS0 at MMIO 0xff180000 (irq = 87) is a rk29_serial.0
[ 2.402365] serial ff180000.serial: membase f0172000
[ 2.403007] ff690000.serial: ttyS2 at MMIO 0xff690000 (irq = 89) is a rk29_serial.2
zzj 发表于 2016-8-30 15:31
我看wiki里面是控制什么backlight的，但是就算我全部都设为disabled还是无法申请，对应的硬件设备是你自 …
你看我发的这个帖子,按照帖子的方法pwm1可以使用http://developer.t-firefly.com/thread-10801-1-1.html