From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yash Shah Subject: [PATCH v7 1/2] pwm: sifive: Add DT documentation for SiFive PWM Controller Date: Thu, 21 Feb 2019 14:41:40 +0530 Message-ID: <1550740301-10097-2-git-send-email-yash.shah@sifive.com> References: <1550740301-10097-1-git-send-email-yash.shah@sifive.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1550740301-10097-1-git-send-email-yash.shah@sifive.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+glpr-linux-riscv=m.gmane.org@lists.infradead.org To: palmer@sifive.com, linux-pwm@vger.kernel.org, linux-riscv@lists.infradead.org Cc: mark.rutland@arm.com, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, robh+dt@kernel.org, sachin.ghadi@sifive.com, Yash Shah , thierry.reding@gmail.com, paul.walmsley@sifive.com List-Id: devicetree@vger.kernel.org DT documentation for PWM controller added. Signed-off-by: Wesley W. Terpstra [Atish: Compatible string update] Signed-off-by: Atish Patra Signed-off-by: Yash Shah --- .../devicetree/bindings/pwm/pwm-sifive.txt | 33 ++++++++++++++++++++++ 1 file changed, 33 insertions(+) create mode 100644 Documentation/devicetree/bindings/pwm/pwm-sifive.txt diff --git a/Documentation/devicetree/bindings/pwm/pwm-sifive.txt b/Documentation/devicetree/bindings/pwm/pwm-sifive.txt new file mode 100644 index 0000000..36447e3 --- /dev/null +++ b/Documentation/devicetree/bindings/pwm/pwm-sifive.txt @@ -0,0 +1,33 @@ +SiFive PWM controller + +Unlike most other PWM controllers, the SiFive PWM controller currently only +supports one period for all channels in the PWM. All PWMs need to run at +the same period. The period also has significant restrictions on the values +it can achieve, which the driver rounds to the nearest achievable period. +PWM RTL that corresponds to the IP block version numbers can be found +here: + +https://github.com/sifive/sifive-blocks/tree/master/src/main/scala/devices/pwm + +Required properties: +- compatible: Should be "sifive,-pwm" and "sifive,pwm". + Supported compatible strings are: "sifive,fu540-c000-pwm" for the SiFive + PWM v0 as integrated onto the SiFive FU540 chip, and "sifive,pwm0" for the + SiFive PWM v0 IP block with no chip integration tweaks. + Please refer to sifive-blocks-ip-versioning.txt for details. +- reg: physical base address and length of the controller's registers +- clocks: Should contain a clock identifier for the PWM's parent clock. +- #pwm-cells: Should be 3. See pwm.txt in this directory + for a description of the cell format. +- interrupts: one interrupt per PWM channel + +Examples: + +pwm: pwm@10020000 { + compatible = "sifive,fu540-c000-pwm", "sifive,pwm0"; + reg = <0x0 0x10020000 0x0 0x1000>; + clocks = <&tlclk>; + interrupt-parent = <&plic>; + interrupts = <42 43 44 45>; + #pwm-cells = <3>; +}; -- 1.9.1