Fix Grid.rotation bug seen in #1888 (#1890)

* When rotated 90/270 degrees led's aren't set appropraitely

When a `Grid.rotate()` is called with 1 or 3, the correct quadrant isn't
chosen.

The issue lies in the function `dev_monome_quad_idx`. This doesn't take
into account rotation state, thus when called with something like:

```c
dev_monome_quad_idx(md->m, 2, 12)
```

It returns quadrant 2. I think we technically want quadrant 1.

We can read the rotation state from the monome device, and use that to
correctly calculate the quadrant with a slightly different formula that
both works for 128 and 256 grids.

* Fix missing variable

* We need to pass in the md reference

* Possible fix for rows/cols not being reset after a rotation

* Don't query grid for rotation status

* Use Grid.update_devices

* Respond to tehn's comments

* Linter

Author: levicole

lua/core/grid.lua

@@ -88,9 +88,11 @@ function Grid.remove(dev) end
 -- @tparam integer val : rotation 0,90,180,270 as [0, 3]
 function Grid:rotation(val)
   _norns.grid_set_rotation(self.dev, val)
+  self.rows = _norns.grid_rows(self.dev)
+  self.cols = _norns.grid_cols(self.dev)
+  Grid.update_devices()
 end
 
-
 --- enable/disable grid tilt.
 -- @tparam integer id : sensor
 -- @tparam integer val : off/on [0, 1]

matron/src/device/device_monome.c

@@ -94,7 +94,10 @@ int dev_monome_init(void *self) {
 }
 
 // calculate quadrant number given x/y
-static inline uint8_t dev_monome_quad_idx(uint8_t x, uint8_t y) {
+static inline uint8_t dev_monome_quad_idx(struct dev_monome *md, uint8_t x, uint8_t y) {
+    // are we a 16x8 grid AND rotated 90 or 270 degrees?
+    if (md->quads == 2 && md->quad_yoff[1] == 8)
+        return ((x > 7) << 1) | (y > 7);
     return ((y > 7) << 1) | (x > 7);
 }
 // calcalate offset into quad data given x/y
@@ -127,7 +130,7 @@ void dev_monome_tilt_disable(struct dev_monome *md, uint8_t sensor) {
 
 // set a given LED value
 void dev_monome_grid_set_led(struct dev_monome *md, uint8_t x, uint8_t y, int8_t val, bool rel) {
-    uint8_t q = dev_monome_quad_idx(x, y);
+    uint8_t q = dev_monome_quad_idx(md, x, y);
     if (rel) {
         md->data[q][dev_monome_quad_offset(x, y)] =
             clamp_range(md->data[q][dev_monome_quad_offset(x, y)] + val, 0, 15);