1 #include <linux/slab.h> 2 #include <linux/io.h> 3 #include <linux/of.h> 4 #include <linux/of_address.h> 5 #include <linux/reset-controller.h> 6 7 #include "reset.h" 8 9 #define rcdev_to_unit(rcdev) container_of(rcdev, struct mmp_clk_reset_unit, rcdev) 10 11 static int mmp_of_reset_xlate(struct reset_controller_dev *rcdev, 12 const struct of_phandle_args *reset_spec) 13 { 14 struct mmp_clk_reset_unit *unit = rcdev_to_unit(rcdev); 15 struct mmp_clk_reset_cell *cell; 16 int i; 17 18 if (WARN_ON(reset_spec->args_count != rcdev->of_reset_n_cells)) 19 return -EINVAL; 20 21 for (i = 0; i < rcdev->nr_resets; i++) { 22 cell = &unit->cells[i]; 23 if (cell->clk_id == reset_spec->args[0]) 24 break; 25 } 26 27 if (i == rcdev->nr_resets) 28 return -EINVAL; 29 30 return i; 31 } 32 33 static int mmp_clk_reset_assert(struct reset_controller_dev *rcdev, 34 unsigned long id) 35 { 36 struct mmp_clk_reset_unit *unit = rcdev_to_unit(rcdev); 37 struct mmp_clk_reset_cell *cell; 38 unsigned long flags = 0; 39 u32 val; 40 41 cell = &unit->cells[id]; 42 if (cell->lock) 43 spin_lock_irqsave(cell->lock, flags); 44 45 val = readl(cell->reg); 46 val |= cell->bits; 47 writel(val, cell->reg); 48 49 if (cell->lock) 50 spin_unlock_irqrestore(cell->lock, flags); 51 52 return 0; 53 } 54 55 static int mmp_clk_reset_deassert(struct reset_controller_dev *rcdev, 56 unsigned long id) 57 { 58 struct mmp_clk_reset_unit *unit = rcdev_to_unit(rcdev); 59 struct mmp_clk_reset_cell *cell; 60 unsigned long flags = 0; 61 u32 val; 62 63 cell = &unit->cells[id]; 64 if (cell->lock) 65 spin_lock_irqsave(cell->lock, flags); 66 67 val = readl(cell->reg); 68 val &= ~cell->bits; 69 writel(val, cell->reg); 70 71 if (cell->lock) 72 spin_unlock_irqrestore(cell->lock, flags); 73 74 return 0; 75 } 76 77 static const struct reset_control_ops mmp_clk_reset_ops = { 78 .assert = mmp_clk_reset_assert, 79 .deassert = mmp_clk_reset_deassert, 80 }; 81 82 void mmp_clk_reset_register(struct device_node *np, 83 struct mmp_clk_reset_cell *cells, int nr_resets) 84 { 85 struct mmp_clk_reset_unit *unit; 86 87 unit = kzalloc(sizeof(*unit), GFP_KERNEL); 88 if (!unit) 89 return; 90 91 unit->cells = cells; 92 unit->rcdev.of_reset_n_cells = 1; 93 unit->rcdev.nr_resets = nr_resets; 94 unit->rcdev.ops = &mmp_clk_reset_ops; 95 unit->rcdev.of_node = np; 96 unit->rcdev.of_xlate = mmp_of_reset_xlate; 97 98 reset_controller_register(&unit->rcdev); 99 } 100