Merge pull request #340 from MLH-Fellowship/229-enable-pwm

Enable DMTimer PWM pins on BBB and PB

Author: pdp7

source/c_pwm.c

@@ -94,6 +94,14 @@ void export_pwm(struct pwm_exp *new_pwm)
     }
 }
 
+int is_dmtimer_pin(pwm_t *p) {   
+    char temp[6];
+    strncpy(temp, p->module, 5);
+    temp[5] = '\0';
+
+    return (strcmp(temp, "timer") == 0);
+}
+
 BBIO_err initialize_pwm(void)
 {
 #ifdef BBBVERSION41  // don't load overlay in 4.1+
@@ -375,16 +383,27 @@ BBIO_err pwm_setup(const char *key, __attribute__ ((unused)) float duty, __attri
         return err;
     }
 
-    err = build_path(ocp_dir, p->chip, pwm_dev_path, sizeof(pwm_dev_path));
-    if (err != BBIO_OK) {
-        syslog(LOG_ERR, "Adafruit_BBIO: pwm_setup: %s couldn't build pwm_dev_path: %i", key, err);
-        return err;
-    }
+    int dmtimer_pin = is_dmtimer_pin(p);
 
-    err = build_path(pwm_dev_path, p->addr, pwm_addr_path, sizeof(pwm_addr_path));
-    if (err != BBIO_OK) {
-        syslog(LOG_ERR, "Adafruit_BBIO: pwm_setup: %s couldn't build pwm_addr_path: %i", key, err);
-        return err;
+    if(!dmtimer_pin) {
+        err = build_path(ocp_dir, p->chip, pwm_dev_path, sizeof(pwm_dev_path));
+        if (err != BBIO_OK) {
+            syslog(LOG_ERR, "Adafruit_BBIO: pwm_setup: %s couldn't build pwm_dev_path: %i", key, err);
+            return err;
+        }
+
+        err = build_path(pwm_dev_path, p->addr, pwm_addr_path, sizeof(pwm_addr_path));
+        if (err != BBIO_OK) {
+            syslog(LOG_ERR, "Adafruit_BBIO: pwm_setup: %s couldn't build pwm_addr_path: %i", key, err);
+            return err;
+        }
+    }
+    else {
+        err = build_path("/sys/devices/platform", p->addr, pwm_addr_path, sizeof(pwm_addr_path));
+        if (err != BBIO_OK) {
+            syslog(LOG_ERR, "Adafruit_BBIO: pwm_setup: %s couldn't build pwm_addr_path, are you sure you've loaded the correct dmtimer device tree overlay?: %i", key, err);
+            return err;
+        }
     }
 
     err = build_path(pwm_addr_path, "pwm/pwmchip", pwm_chip_path, sizeof(pwm_chip_path));
@@ -397,10 +416,10 @@ BBIO_err pwm_setup(const char *key, __attribute__ ((unused)) float duty, __attri
     syslog(LOG_DEBUG, "Adafruit_BBIO: pwm_start: key: %s, pwm_path: %s", key, pwm_path);
 
     //pwm with udev patch
-    snprintf(pwm_path_udev, sizeof(pwm_path_udev), "%s/pwm-%c:%d", pwm_chip_path, pwm_path[66], p->index);
+    snprintf(pwm_path_udev, sizeof(pwm_path_udev), "%s/pwm-%c:%d", pwm_chip_path, dmtimer_pin ? pwm_path[47] : pwm_path[66], p->index);
     syslog(LOG_DEBUG, "Adafruit_BBIO: pwm_start: key: %s, pwm_path_udev: %s", key, pwm_path_udev);
     //ecap output with udev patch
-    snprintf(ecap_path_udev, sizeof(ecap_path_udev), "%s/pwm-%c:%d", pwm_chip_path, pwm_path[66], p->index);
+    snprintf(ecap_path_udev, sizeof(ecap_path_udev), "%s/pwm-%c:%d", pwm_chip_path, dmtimer_pin ? pwm_path[47] : pwm_path[66], p->index);
     syslog(LOG_DEBUG, "Adafruit_BBIO: pwm_start: key: %s, ecap_path_udev: %s", key, ecap_path_udev);
 
     // Export PWM if hasn't already been

source/common.c

@@ -81,10 +81,10 @@ pins_t table[] = {
   { "GPIO1_7", "P8_4", 39, -1, -1},
   { "GPIO1_2", "P8_5", 34, -1, -1},
   { "GPIO1_3", "P8_6", 35, -1, -1},
-  { "TIMER4", "P8_7", 66, -1, -1},
-  { "TIMER7", "P8_8", 67, -1, -1},
-  { "TIMER5", "P8_9", 69, -1, -1},
-  { "TIMER6", "P8_10", 68, -1, -1},
+  { "TIMER4", "P8_7", 66, 2, -1},
+  { "TIMER7", "P8_8", 67, 2, -1},
+  { "TIMER5", "P8_9", 69, 2, -1},
+  { "TIMER6", "P8_10", 68, 2, -1},
   { "GPIO1_13", "P8_11", 45, -1, -1},
   { "GPIO1_12", "P8_12", 44, -1, -1},
   { "EHRPWM2B", "P8_13", 23, 4, -1},
@@ -206,15 +206,15 @@ pins_t table[] = {
   { "VREFN", "P1_17", 0, -1, -1},
   { "VREFP", "P1_18", 0, -1, -1},
   { "AIN0", "P1_19", 0, -1, 0},
-  { "GPIO0_20", "P1_20", 20, -1, -1},
+  { "GPIO0_20", "P1_20", 20, 4, -1},
   { "AIN1", "P1_21", 0, -1, 1},
   { "GND", "P1_22", 0, -1, -1},
   { "AIN2", "P1_23", 0, -1, 2},
   { "VOUT-5V", "P1_24", 0, -1, -1},
   { "AIN3", "P1_25", 0, -1, 3},
-  { "I2C2_SDA", "P1_26", 12, -1, -1},
+  { "I2C2_SDA", "P1_26", 12, 1, -1},
   { "AIN4", "P1_27", 0, -1, 4},
-  { "I2C2_SCL", "P1_28", 13, -1, -1},
+  { "I2C2_SCL", "P1_28", 13, 1, -1},
   { "GPIO3_21", "P1_29", 117, -1, -1},
   { "UART0_TXD", "P1_30", 43, -1, -1},
   { "GPIO3_18", "P1_31", 114, -1, -1},
@@ -249,11 +249,11 @@ pins_t table[] = {
   { "GPIO1_12", "P2_24", 44, -1, -1},
   { "SPI1_CS0", "P2_25", 41, -1, -1},
   { "RESET#", "P2_26", 0, -1, -1},
-  { "SPI1_D0", "P2_27", 40, -1, -1},
+  { "SPI1_D0", "P2_27", 40, 5, -1},
   { "GPIO3_20", "P2_28", 116, -1, -1},
   { "SPI1_SCLK", "P2_29", 7, -1, -1},
   { "GPIO3_17", "P2_30", 113, -1, -1},
-  { "SPI1_CS1", "P2_31", 19, -1, -1},
+  { "SPI1_CS1", "P2_31", 19, 2, -1},
   { "GPIO3_16", "P2_32", 112, -1, -1},
   { "GPIO1_13", "P2_33", 45, -1, -1},
   { "GPIO3_19", "P2_34", 115, -1, -1},
@@ -305,12 +305,21 @@ pwm_t pwm_table[] = {
   { "ehrpwm0", 1, 1, 1, "ehrpwm.0:1", "EHRPWM0B", "48300000", "48300200", "P9_29"},
   { "ehrpwm0", 0, 0, 1, "ehrpwm.0:0", "EHRPWM0A", "48300000", "48300200", "P9_31"},
   {   "ecap0", 2, 0, 0, "ecap.0",     "ECAPPWM0", "48300000", "48300100", "P9_42"},
+  { "timer4", 0, 0, 2, "", "", "", "dmtimer-pwm-4", "P8_7" },
+  { "timer7", 0, 0, 2, "", "", "", "dmtimer-pwm-7", "P8_8" },
+  { "timer5", 0, 0, 2, "", "", "", "dmtimer-pwm-5", "P8_9" },
+  { "timer6", 0, 0, 2, "", "", "", "dmtimer-pwm-6", "P8_10" },
   { "ehrpwm0", 0, 0, 1, "ehrpwm.0:0", "EHRPWM0A", "48300000", "48300200", "P1_8"},
   { "ehrpwm0", 0, 0, 1, "ehrpwm.0:0", "EHRPWM0A", "48300000", "48300200", "P1_36"},
   { "ehrpwm0", 1, 1, 1, "ehrpwm.0:1", "EHRPWM0B", "48300000", "48300200", "P1_10"},
   { "ehrpwm0", 1, 1, 1, "ehrpwm.0:1", "EHRPWM0B", "48300000", "48300200", "P1_33"},
   { "ehrpwm1", 3, 0, 6, "ehrpwm.1:0", "EHRPWM1A", "48302000", "48302200", "P2_1"},
   { "ehrpwm2", 6, 1, 3, "ehrpwm.2:1", "EHRPWM2B", "48304000", "48304200", "P2_3"},
+  { "timer7", 0, 0, 4, "", "", "", "dmtimer-pwm-7", "P1_20" },
+  { "timer6", 0, 0, 1, "", "", "", "dmtimer-pwm-6", "P1_26" },
+  { "timer5", 0, 0, 1, "", "", "", "dmtimer-pwm-5", "P1_28" },
+  { "timer7", 0, 0, 5, "", "", "", "dmtimer-pwm-7", "P2_27" },
+  { "timer4", 0, 0, 2, "", "", "", "dmtimer-pwm-4", "P2_31" },
   { NULL, 0, 0, 0, NULL, NULL, NULL, NULL, NULL }
 };