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linux/Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt

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pwm: Add TI PWM subsystem driver 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>
2012-11-27 16:48:06 +08:00
TI SOC based PWM Subsystem
Required properties:
ARM: dts: am437x: Add missing compatibles to PWM binding documents There are several SOC specific compatibles for ECAP, EHRPWM and PWMMS that are in use but aren't properly documented. Therefore, fix this by adding the compatibles to the appropriate binding documents. While at it make minor corrections to the binding document. Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Tony Lindgren <tony@atomide.com>
2016-05-03 23:56:48 +08:00
- compatible: Must be "ti,<soc>-pwmss".
for am33xx - compatible = "ti,am33xx-pwmss";
for am4372 - compatible = "ti,am4372-pwmss","ti,am33xx-pwmss";
ARM: dts: DRA7: Add dt nodes for PWMSS Add PWMSS device tree nodes for DRA7 SoC family and add documentation for dt bindings. Signed-off-by: Vignesh R <vigneshr@ti.com> [fcooper@ti.com: Add eCAP and use updated bindings for PWMSS and ePWM] Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Tony Lindgren <tony@atomide.com>
2016-05-03 23:56:55 +08:00
for dra746 - compatible = "ti,dra746-pwmss", "ti,am33xx-pwmss"
ARM: dts: am437x: Add missing compatibles to PWM binding documents There are several SOC specific compatibles for ECAP, EHRPWM and PWMMS that are in use but aren't properly documented. Therefore, fix this by adding the compatibles to the appropriate binding documents. While at it make minor corrections to the binding document. Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Tony Lindgren <tony@atomide.com>
2016-05-03 23:56:48 +08:00
pwm: Add TI PWM subsystem driver 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>
2012-11-27 16:48:06 +08:00
- reg: physical base address and size of the registers map.
- address-cells: Specify the number of u32 entries needed in child nodes.
Should set to 1.
- size-cells: specify number of u32 entries needed to specify child nodes size
in reg property. Should set to 1.
- ranges: describes the address mapping of a memory-mapped bus. Should set to
physical address map of child's base address, physical address within
parent's address space and length of the address map. For am33xx,
3 set of child register maps present, ECAP register space, EQEP
register space, EHRPWM register space.
Also child nodes should also populated under PWMSS DT node.
Example:
ARM: dts: am437x: Add missing compatibles to PWM binding documents There are several SOC specific compatibles for ECAP, EHRPWM and PWMMS that are in use but aren't properly documented. Therefore, fix this by adding the compatibles to the appropriate binding documents. While at it make minor corrections to the binding document. Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Tony Lindgren <tony@atomide.com>
2016-05-03 23:56:48 +08:00
epwmss0: epwmss@48300000 { /* PWMSS for am33xx */
pwm: Add TI PWM subsystem driver 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>
2012-11-27 16:48:06 +08:00
compatible = "ti,am33xx-pwmss";
reg = <0x48300000 0x10>;
ti,hwmods = "epwmss0";
#address-cells = <1>;
#size-cells = <1>;
status = "disabled";
ranges = <0x48300100 0x48300100 0x80 /* ECAP */
0x48300180 0x48300180 0x80 /* EQEP */
0x48300200 0x48300200 0x80>; /* EHRPWM */
/* child nodes go here */
};
ARM: dts: am437x: Add missing compatibles to PWM binding documents There are several SOC specific compatibles for ECAP, EHRPWM and PWMMS that are in use but aren't properly documented. Therefore, fix this by adding the compatibles to the appropriate binding documents. While at it make minor corrections to the binding document. Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Tony Lindgren <tony@atomide.com>
2016-05-03 23:56:48 +08:00
epwmss0: epwmss@48300000 { /* PWMSS for am4372 */
compatible = "ti,am4372-pwmss","ti,am33xx-pwmss"
reg = <0x48300000 0x10>;
ti,hwmods = "epwmss0";
#address-cells = <1>;
#size-cells = <1>;
status = "disabled";
ranges = <0x48300100 0x48300100 0x80 /* ECAP */
0x48300180 0x48300180 0x80 /* EQEP */
0x48300200 0x48300200 0x80>; /* EHRPWM */
/* child nodes go here */
};
ARM: dts: DRA7: Add dt nodes for PWMSS Add PWMSS device tree nodes for DRA7 SoC family and add documentation for dt bindings. Signed-off-by: Vignesh R <vigneshr@ti.com> [fcooper@ti.com: Add eCAP and use updated bindings for PWMSS and ePWM] Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Tony Lindgren <tony@atomide.com>
2016-05-03 23:56:55 +08:00
epwmss0: epwmss@4843e000 { /* PWMSS for DRA7xx */
compatible = "ti,dra746-pwmss", "ti,am33xx-pwmss";
reg = <0x4843e000 0x30>;
ti,hwmods = "epwmss0";
#address-cells = <1>;
#size-cells = <1>;
ranges;
/* child nodes go here */
};