lwn.git - Linux kernel documentation tree maintained by Jonathan Corbet

Age	Commit message (Collapse)	Author
2016-07-11	pwm: pwm-ti*: Remove support for local clock gating	Cooper Jr., Franklin
	The PWMSS local clock gating registers have no real purpose on OMAP ARM devices. These registers were left over registers from DSP IP where the PRCM doesn't exist. There is a silicon bug where gating and ungating clocks don't function properly. TRMs will be update to indicate that these registers shouldn't be touched. Therefore, all code that accesses the PWMSS_CLKCONFIG or PWMSS_CLKSTATUS will be removed by this patch with zero loss of functionality by the ECAP and EPWM drivers. Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-03-22	pwm: davinci: Add Kconfig support for ECAP & EHRPWM devices	Philip Avinash
	Add EHRPWM and ECAP support build support for DAVINCI_DA8XX platforms. Also, since DAVINCI platforms doesn't support TI-PWM-Subsystem module, remove the select option for CONFIG_PWM_TIPWMSS. Also, update CONFIG_PWM_TIPWMSS compiler directive appropriately in pwm-tipwmss.h to fix the below compiler error upon removal of CONFIG_PWM_TIPWMSS for DAVINCI platforms. drivers/pwm/pwm-tiecap.c: In function 'ecap_pwm_probe': drivers/pwm/pwm-tiecap.c:263:4: error: 'PWMSS_ECAPCLK_EN' undeclared (first use in this function) drivers/pwm/pwm-tiecap.c:263:4: note: each undeclared identifier is reported only once for each function it appears in drivers/pwm/pwm-tiecap.c:264:17: error: 'PWMSS_ECAPCLK_EN_ACK' undeclared (first use in this function) drivers/pwm/pwm-tiecap.c: In function 'ecap_pwm_remove': drivers/pwm/pwm-tiecap.c:291:49: error: 'PWMSS_ECAPCLK_STOP_REQ' undeclared (first use in this function) make[2]: * [drivers/pwm/pwm-tiecap.o] Error 1 make[1]: * [drivers/pwm] Error 2 make: *** [drivers] Error 2 Signed-off-by: Philip Avinash <avinashphilip@ti.com> Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2012-11-28	pwm: Add TI PWM subsystem driver	Philip, Avinash
	In some platforms (like am33xx), PWM sub modules (ECAP, EHRPWM, EQEP) are integrated to PWM subsystem. These PWM submodules has resources shared and only one register bit-field is provided to control module/clock enable/disable, makes it difficult to handle common resources from independent PWMSS submodule drivers. So the solution here implemented in this patch is, to create driver for PWMSS and take the role of parent driver for PWM submodules. PWMSS parent driver enumerates all the child nodes under PWMSS module. Also symbol "pwmss_submodule_state_change" exported to enable clock gating for individual PWMSS submodules, and submodule drivers has to enable clock gating from their drivers. As this is only supported during DT boot, the parent/child relationship is created and populated in DT execution flow. The only required change is inside DTS file, making EHRPWM & ECAP as a child to PWMSS node. Signed-off-by: Philip, Avinash <avinashphilip@ti.com> Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>